Method for transmitting and receiving srs and communication device therefor

ABSTRACT

A method for transmitting a sounding reference signal (SRS) by a by a user equipment (UE) includes: receiving, from a base station, first information on a number of SRS symbols configured for one slot and second information on a number of repetitions of symbols configured for transmission of an SRS; determining whether the number of repetitions is greater than the number of the SRS symbols; when the number of repetitions is greater than the number of the SRS symbols, determining the number of repetitions of the symbols by a value identical to the number of the SRS symbols; and transmitting the SRS based on the determined number of repetitions. The UE is capable of communicating with at least one of another UE, a UE related to an autonomous driving vehicle, a base station, or a network.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/843,407, filed on Apr. 8, 2020, which is a continuation ofInternational Application No. PCT/KR2018/011890, filed on Oct. 10, 2018,which claims the benefit of U.S. Provisional Application No. 62/571,167,filed on Oct. 11, 2017. The disclosures of the prior applications areincorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to wireless communication and, moreparticularly, to a method of transmitting and receiving a soundingreference signal (SRS) and a communication apparatus therefor.

BACKGROUND

When a new radio access technology (RAT) system is introduced, as moreand more communication devices require larger communication capacity,there is a need for improved mobile broadband communication as comparedto existing RAT.

In addition, massive machine type communications (MTC) connected to aplurality of devices and things to provide various services anytime andanywhere is one of main issues to be considered in next-generationcommunication. In addition, communication system design consideringservices/UEs sensitive to reliability and latency has been discussed. Assuch, New RAT will provide services considering enhanced mobilebroadband communication (eMBB), massive MTC (mMTC), URLLC(Ultra-Reliable Low-Latency Communication), etc. In a next-generation 5Gsystem, scenarios may be divided into Enhanced Mobile Broadband(eMBB)/Ultra-reliable Machine-Type Communications (uMTC)/MassiveMachine-Type Communications (mMTC), etc. eMBB is a next-generationmobile communication scenario having high spectrum efficiency, high userexperienced data rate, high peak data rate, etc., uMTC is anext-generation mobile communication scenario having ultra-reliability,ultra-low latency, ultra-high availability, etc. (e.g., V2X, emergencyservice, remote control), and mMTC is a next-generation mobilecommunication scenario having low cost, low energy, short packet, andmassive connectivity (e.g., IoT).

SUMMARY

An object of the present disclosure is to provide a method oftransmitting a sounding reference signal (SRS) by a user equipment (UE).

Another object of the present disclosure is to provide a method ofreceiving an SRS by a base station (BS).

Another object of the present disclosure is to provide a UE fortransmitting an SRS.

Another object of the present disclosure is to provide a BS forreceiving an SRS.

It will be appreciated by persons skilled in the art that the objectsthat could be achieved with the present disclosure are not limited towhat has been particularly described hereinabove and the above and otherobjects that the present disclosure could achieve will be more clearlyunderstood from the following detailed description.

According to an aspect of the present disclosure, provided herein is amethod of transmitting a sounding reference signal (SRS) by a userequipment (UE), including receiving first information on the number ofSRS symbols configured in one slot and second information on therepetition number of symbols configured for SRS transmission from a basestation (BS); determining whether the repetition number of symbolsconfigured for SRS transmission is greater than the number of SRSsymbols configured in the one slot; determining the repetition number ofsymbols configured for SRS transmission as a value equal to the numberof SRS symbols configured in the one slot, based on the repetitionnumber of symbols configured for SRS transmission greater than thenumber of SRS symbols configured in the one slot; and transmitting theSRS based on the determined repetition number of symbols configured forSRS transmission.

The method may further include receiving information on a firstparameter value indicating SRS bandwidth and information on a secondparameter value indicating SRS frequency hopping bandwidth from the BS.The SRS may be transmitted by being hopped at a slot level based on thefirst parameter value greater than the second parameter value. Thedetermined repetition number of symbols configured for SRS transmissionmay be a repetition number over at least two slots, and the SRS may betransmitted over the at least two slots. The determined repetitionnumber of symbols configured for SRS transmission may be a repetitionnumber over the one slot, and the SRS is transmitted over the one slotwithout frequency hopping.

The first information and the second information may be received throughradio resource control (RRC) signaling.

In another aspect of the present disclosure, provided herein is a methodof receiving a sounding reference signal (SRS) by a base station (BS),including transmitting first information on the number of SRS symbolsconfigured in one slot and second information on the repetition numberof symbols configured for SRS transmission to a user equipment (UE);determining the repetition number of symbols configured for SRStransmission as a value equal to the number of SRS symbols configured inthe one slot, based on the repetition number of symbols configured forSRS transmission greater than the number of SRS symbols configured inthe one slot; and receiving the SRS based on the determined repetitionnumber of symbols configured for SRS transmission.

The method may further include transmitting information on a firstparameter value indicating SRS bandwidth and information on a secondparameter value indicating SRS frequency hopping bandwidth to the UE.The SRS may be received by being hopped at a slot level based on thefirst parameter value greater than the second parameter value.

The determined repetition number of symbols configured for SRStransmission may be a repetition number over at least two slots, and theSRS may be received over the at least two slots. The determinedrepetition number of symbols configured for SRS transmission may be arepetition number over the one slot, and the SRS may be received overthe one slot without frequency hopping. The first information and thesecond information may be transmitted through radio resource control(RRC) signaling.

In another aspect of the present disclosure, provided herein is a userequipment (UE) for transmitting a sounding reference signal (SRS),including a receiver configured to receive first information on thenumber of SRS symbols configured in one slot and second information onthe repetition number of symbols configured for SRS transmission from abase station (BS); a processor configured to determine whether therepetition number of symbols configured for SRS transmission is greaterthan the number of SRS symbols configured in the one slot, and determinethe repetition number of symbols configured for SRS transmission as avalue equal to the number of SRS symbols configured in the one slot,based on the repetition number of symbols configured for SRStransmission greater than the number of SRS symbols configured in theone slot; and a transmitter configured to transmit the SRS based on thedetermined repetition number of symbols configured for SRS transmission.

The receiver may receive information on a first parameter valueindicating SRS bandwidth and information on a second parameter valueindicating SRS frequency hopping bandwidth from the BS. The processormay control the transmitter to transmit the SRS by being hopped at aslot level based on the first parameter value greater than the secondparameter value. The receiver may receive the first information and thesecond information through radio resource control (RRC) signaling.

In another aspect of the present disclosure, provided herein is basestation (BS) for receiving a sounding reference signal (SRS), includinga transmitter configured to transmit first information on the number ofSRS symbols configured in one slot and second information on therepetition number of symbols configured for SRS transmission to a userequipment (UE); a processor configured to determine the repetitionnumber of symbols configured for SRS transmission as a value equal tothe number of SRS symbols configured in the one slot, based on therepetition number of symbols configured for SRS transmission greaterthan the number of SRS symbols configured in the one slot; and areceiver configured to receive the SRS based on the determinedrepetition number of symbols configured for SRS transmission. Thetransmitter may transmit information on a first parameter valueindicating SRS bandwidth and information on a second parameter valueindicating SRS frequency hopping bandwidth to the UE, and the processormay control the receiver to receive the SRS by being hopped at a slotlevel based on the first parameter value greater than the secondparameter value.

According to an embodiment of the present disclosure, a UE and a BS mayefficiently perform sounding reference signal (SRS) transmission(inter-slot hopping may be performed) and reception without errors evenwhen r>N_(symbol).

The effects that can be achieved with the present disclosure are notlimited to what has been particularly described hereinabove and otheradvantages not described herein will be more clearly understood bypersons skilled in the art from the following detailed description ofthe present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure, illustrate embodiments of thedisclosure and together with the description serve to explain theprinciple of the disclosure.

FIG. 1 is a diagram illustrating a wireless communication system forimplementing the present disclosure.

FIG. 2A is a diagram illustrating TXRU virtualization model option 1(sub-array model) and FIG. 2B is a diagram illustrating TXRUvirtualization model option 2 (full connection model).

FIG. 3 is a block diagram for hybrid beamforming.

FIG. 4 is a diagram illustrating beams mapped to BRS symbols in hybridbeamforming.

FIG. 5 is a diagram illustrating symbol/sub-symbol alignment betweendifferent numerologies.

FIG. 6 is a diagram illustrating performance of 52-lengthautocorrelation using two 26-length Golay complementary sequence pairs;

FIG. 7 is a diagram illustrating cross-correlation between sequenceshaving different CSs in a 52-length Golay sequence;

FIGS. 8A and 8B are diagrams illustrating cross-correlation andcubic-metric evaluations of ZC, Golay, and PN sequences;

FIG. 9 is a diagram illustrating an LTE hopping pattern(n_(s)=1→n_(s)=4);

FIG. 10 is a diagram illustrating multi-symbol SRS triggering for uplinkbeam management;

FIG. 11 is a diagram illustrating a combination{TC(α₁(l′,n_(s))),CS(α₁(l′,n_(s)))} of SRS sequence generationparameters according to a hopping pattern α₁(l′,n_(s));

FIG. 12 is a diagram illustrating occurrence of collision between UEs atthe time of hopping;

FIG. 13 illustrates an example of transmitting symbol-level hoppingparameters through RRC signaling and transmitting slot-level hoppingparameter through DCI signaling;

FIG. 14 is a diagram illustrating the case in which a BS transmitsintra-slot hopping parameters through DCI signaling and transmitsinter-slot hopping parameters through RRC signaling;

FIG. 15 illustrates the case where a BS transmits symbol-level hoppingparameters through RRC signaling and transmits slot-level hoppingparameters through DCI according to Proposal 2-1-2;

FIG. 16 is a diagram illustrating an example of transmitting parametersfor symbol-level hopping configuration and parameters for slot-levelhopping configuration through RRC signaling according to Proposal 2-1-3;

FIG. 17 is a diagram illustrating an example of applying differentsymbol-level hopping patterns according to hopping cycle;

FIG. 18 is a diagram illustrating an example of applying the samesymbol-level hopping pattern at the time of aperiodic SRS transmission;

FIG. 19 is a diagram illustrating an example of applying differentsymbol-level hopping patterns at the time of aperiodic SRS transmission;

FIG. 20 is a diagram illustrating an example of applying differentsymbol-level hopping patterns (hopping over a partial band) at the timeof aperiodic SRS transmission;

FIG. 21 is a diagram illustrating an example of applying differentsymbol-level hopping pattern (hopping over a specific subband) at thetime of aperiodic SRS transmission;

FIG. 22 is a diagram illustrating SRS transmission according to requestfield transmission using a hopping parameter set at the time ofaperiodic SRS transmission;

FIG. 23 is a diagram illustrating hoping when a triggering counter N=3;

FIG. 24 is a diagram illustrating symbol-level hopping when a repetitionnumber is 2 (r=2);

FIG. 25 is a diagram illustrating a hopping pattern according to thenumber of symbols of an SRS;

FIG. 26 is a diagram illustrating a hopping pattern according to thenumber of symbols of an SRS (when the number of symbols of the SRS in anSRS slot is less than a symbol hopping cycle);

FIG. 27 is a diagram illustrating description of Case 1-1;

FIG. 28 is a diagram illustrating description of Case 1-2;

FIG. 29 is a diagram illustrating description of Case 2;

FIGS. 30A and 30B are diagrams illustrating description of Case 3;

FIG. 31 is a diagram illustrating configuration of a fixed SRS resourceposition at the time of periodic/aperiodic SRS transmission;

FIG. 32 is a diagram illustrating configuration of hopping betweenpartial bands at the time of periodic/aperiodic triggering;

FIG. 33 is a diagram illustrating configuration of hopping betweenpartial bands at the time of periodic/aperiodic triggering;

FIG. 34 is a diagram illustrating an example of changing an SRS resourceposition at the time of periodic/aperiodic triggering (a partial band isfixed);

FIG. 35 is a diagram illustrating an example of changing an SRS resourceposition at the time of periodic/aperiodic triggering (a partial band isvariable); and

FIGS. 36A and 36B are diagrams illustrating a symbol-level hoppingpattern considering RF retuning of a UE having narrow band RFcapability.

FIG. 37 is a diagram illustrating a procedure of transmitting an SRS bya UE in relation to Proposal 6;

FIG. 38 is a diagram illustrating a procedure of receiving an SRS by aBS in relation to Proposal 6; and

FIG. 39 is a block diagram of a UE for transmitting an SRS and a BS forreceiving an SRS in relation to Proposal 6.

DETAILED DESCRIPTION

Reference will now be made in detail to the preferred embodiments of thepresent disclosure, examples of which are illustrated in theaccompanying drawings. In the following detailed description of thedisclosure includes details to help the full understanding of thepresent disclosure. Yet, it is apparent to those skilled in the art thatthe present disclosure can be implemented without these details. Forinstance, although the following descriptions are made in detail on theassumption that a mobile communication system includes 3GPP LTE system,the following descriptions are applicable to other random mobilecommunication systems in a manner of excluding unique features of the3GPP LTE.

Occasionally, to prevent the present disclosure from getting vaguer,structures and/or devices known to the public are skipped or can berepresented as block diagrams centering on the core functions of thestructures and/or devices. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.

Besides, in the following description, assume that a terminal is acommon name of such a mobile or fixed user stage device as a userequipment (UE), a mobile station (MS), an advanced mobile station (AMS)and the like. And, assume that a base station (BS) is a common name ofsuch a random node of a network stage communicating with a terminal as aNode B (NB), an eNode B (eNB), an access point (AP), gNode B and thelike. Although the present specification is described based on IEEE802.16m system, contents of the present disclosure may be applicable tovarious kinds of other communication systems.

In a mobile communication system, a user equipment is able to receiveinformation in downlink and is able to transmit information in uplink aswell. Information transmitted or received by the user equipment node mayinclude various kinds of data and control information. In accordancewith types and usages of the information transmitted or received by theuser equipment, various physical channels may exist.

The following descriptions are usable for various wireless accesssystems including CDMA (code division multiple access), FDMA (frequencydivision multiple access), TDMA (time division multiple access), OFDMA(orthogonal frequency division multiple access), SC-FDMA (single carrierfrequency division multiple access) and the like. CDMA can beimplemented by such a radio technology as UTRA (universal terrestrialradio access), CDMA 2000 and the like. TDMA can be implemented with sucha radio technology as GSM/GPRS/EDGE (Global System for Mobilecommunications)/General Packet Radio Service/Enhanced Data Rates for GSMEvolution). OFDMA can be implemented with such a radio technology asIEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, E-UTRA (EvolvedUTRA), etc. UTRA is a part of UMTS (Universal Mobile TelecommunicationsSystem). 3GPP (3rd Generation Partnership Project) LTE (long termevolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA. The 3GPPLTE employs OFDMA in DL and SC-FDMA in UL. And, LTE-A (LTE-Advanced) isan evolved version of 3GPP LTE.

Moreover, in the following description, specific terminologies areprovided to help the understanding of the present disclosure. And, theuse of the specific terminology can be modified into another form withinthe scope of the technical idea of the present disclosure.

FIG. 1 is a diagram illustrating a wireless communication system forimplementing the present disclosure.

Referring to FIG. 1, the wireless communication system includes a basestation (BS) 10 and one or more UEs 20. On downlink (DL), a transmittermay be a part of the BS and a receiver may be a part of the UEs 20. Onuplink (UL), the BS 10 may include a processor 11, a memory 12, and aradio frequency (RF) unit 13 (a transmitter and a receiver). Theprocessor 11 may be configured to implement the proposed proceduresand/or methods disclosed in the present application. The memory 12 iscoupled to the processor 11 to store a variety of information foroperating the processor 11. The RF unit 13 is coupled to the processor11 to transmit and/or receive a radio signal. The UE 20 may include aprocessor 21, a memory 22, and an RF unit 23 (a transmitter and areceiver). The processor 21 may be configured to implement the proposedprocedures and/or methods disclosed in the present application. Thememory 22 is coupled to the processor 21 to store a variety ofinformation for operating the processor 21. The RF unit 23 is coupled tothe processor 21 to transmit and/or receive a radio signal. Each of theBS 10 and/or the UE 20 may have a single antenna or multiple antennas.When at least one of the BS 10 and the UE 20 has multiple antennas, thewireless communication system may be called a multiple input multipleoutput (MIMO) system.

In the present specification, while the processor 21 of the UE and theprocessor 11 of the BS perform operations of processing signals anddata, except for a function of receiving and transmitting signals,performed respectively by the UE 20 and the BS 10, and a storagefunction, the processors 11 and 21 will not be particularly mentionedhereinbelow, for convenience of description. Although the processors 11and 21 are not particularly mentioned, it may be appreciated thatoperations such as data processing other than signal reception ortransmission may be performed by the processors 11 and 21.

Layers of a radio interface protocol between the UE 20 and the BS 10 ofthe wireless communication system (network) may be classified into afirst layer L1, a second layer L2, and a third layer L3, based on 3lower layers of open systems interconnection (OSI) model well known incommunication systems. A physical layer belongs to the first layer andprovides an information transfer service via a physical channel. A radioresource control (RRC) layer belongs to the third layer and providescontrol radio resources between the UE and the network. The UE 10 andthe BS 20 may exchange RRC messages with each other through the wirelesscommunication network and the RRC layers.

Analog Beamforming

In a millimeter wave (mmW) system, since a wavelength becomes shorter, aplurality of antenna elements may be installed in the same area. Thatis, considering that the wavelength at a band of 30 GHz is 1 cm, a totalof 64 (8×8) antenna elements may be installed in a 4*4 cm panel atintervals of 0.5 lambda (wavelength) in the case of a 2-dimensionalarray. Therefore, in the mmW system, it is possible to improve coverageor throughput by increasing beamforming (BF) gain using multiple antennaelements.

In this case, each antenna element may include a transceiver unit (TXRU)to enable adjustment of transmit power and phase per antenna element. Bydoing so, each antenna element may perform independent beamforming perfrequency resource. However, installing TXRUs in all of the about 100antenna elements is less feasible in terms of cost. Therefore, a methodof mapping a plurality of antenna elements to one TXRU and adjusting thedirection of a beam using an analog phase shifter has been considered.However, this method is disadvantageous in that frequency selectivebeamforming is impossible because only one beam direction is generatedover the full band.

As an intermediate form of digital BF and analog BF, hybrid BF with BTXRUs that are fewer than Q antenna elements may be considered. In thecase of the hybrid BF, the number of beam directions that may betransmitted at the same time is limited to B or less, which depends onhow B TXRUs and Q antenna elements are connected.

FIG. 2A is a diagram illustrating TXRU virtualization model option 1(sub-array model) and FIG. 2B is a diagram illustrating TXRUvirtualization model option 2 (full connection model).

FIGS. 2A and 2B show representative examples of a method of connectingTXRUs and antenna elements. Here, the TXRU virtualization model shows arelationship between TXRU output signals and antenna element outputsignals. FIG. 2A shows a method of connecting TXRUs to sub-arrays. Inthis case, one antenna element is connected to one TXRU. In contrast,FIG. 2B shows a method of connecting all TXRUs to all antenna elements.In this case, all antenna elements are connected to all TXRUs. In FIGS.2A and 2B, W indicates a phase vector weighted by an analog phaseshifter. That is, W is a major parameter determining the direction ofthe analog beamforming. In this case, the mapping relationship betweenchannel state information-reference signal (CSI-RS) antenna ports andTXRUs may be 1-to-1 or 1-to-many.

Hybrid Beamforming

FIG. 3 is a block diagram for hybrid beamforming.

If a plurality of antennas is used in a new RAT system, a hybridbeamforming scheme which is a combination of digital beamforming andanalog beamforming may be used. At this time, analog beamforming (or RFbeamforming) means operation of performing precoding (or combining) atan RF stage. In the hybrid beamforming scheme, each of a baseband stageand an RF stage uses a precoding (or combining) method, thereby reducingthe number of RF chains and the number of D/A (or A/D) converters andobtaining performance similar to performance of digital beamforming. Forconvenience of description, as shown in FIG. 3, the hybrid beamformingstructure may be expressed by N transceivers (TXRUs) and M physicalantennas. Digital beamforming for L data layers to be transmitted by atransmission side may be expressed by an N×L matrix, N digital signalsare converted into analog signals through TXRUs and then analogbeamforming expressed by an M×N matrix is applied.

At this time, in FIG. 3, the number of digital beams is L and the numberof analog beams is N. Further, in the new RAT system, a BS is designedto change analog beamforming in symbol units, thereby supporting moreefficient beamforming for a UE located in a specific region.Furthermore, in FIG. 3, when N TXRUs and M RF antennas are defined asone antenna panel, up to a method of introducing a plurality of antennapanels, to which independent hybrid beamforming is applicable, is beingconsidered in the new RAT system.

When the BS uses a plurality of analog beams, since an analog beam whichis advantageous for signal reception may differ between UEs, the BS mayconsider beam sweeping operation in which the plurality of analog beams,which will be applied by the BS in a specific subframe (SF), is changedaccording to symbol with respect to at least synchronization signals,system information, paging, etc. such that all UEs have receptionopportunities.

FIG. 4 is a diagram illustrating beams mapped to BRS symbols in hybridbeamforming.

FIG. 4 shows the beam sweeping operation with respect to synchronizationsignals and system information in a downlink (DL) transmissionprocedure. In FIG. 4, a physical resource (or physical channel) throughwhich the system information of the new RAT system is transmitted in abroadcast manner is named xPBCH (physical broadcast channel). At thistime, analog beams belonging to different antenna panels may besimultaneously transmitted within one symbol, and, in order to measure achannel per analog beam, as shown in FIG. 4, a method of introducing abeam reference signal (BRS) which is an RS transmitted by applying asingle analog beam (corresponding to a specific analog panel) may beconsidered. The BRS may be defined with respect to a plurality ofantenna ports and each antenna port of the BRS may correspond to asingle analog beam. Although the RS used to measure the beam is givenBRS in FIG. 5, the RS used to measure the beam may be named anothername. At this time, unlike the BRS, a synchronization signal or xPBCHmay be transmitted by applying all analog beams of an analog beam group,such that an arbitrary UE properly receives the synchronization signalor xPBCH.

FIG. 5 is a diagram illustrating symbol/sub-symbol alignment betweendifferent numerologies.

New RAT(NR) Numerology Characteristics

In NR, a method of supporting scalable numerology is being considered.That is, a subcarrier spacing of NR is (2n×15) kHz and n is an integer.From the nested viewpoint, a subset or a superset (at least 15, 30, 60,120, 240, and 480 kHz) is being considered as a main subcarrier spacing.Symbol or sub-symbol alignment between different numerologies wassupported by performing control to have the same CP overhead ratio.

In addition, the numerology is determined in a structure for dynamicallyallocating time/frequency granularity according to services (eMBB, URLLCand mMTC) and scenarios (high speed, etc.).

Bandwidth Dependent/Non-Dependent Sequence for Orthogonalization

In an LTE system, an SRS is differently designed according to soundingbandwidth. That is, a computer-generated sequence is used when asequence having length 24 or less is designed and a Zadoff-Chu (ZC)sequence is used in the case of a sequence of length 36 (3 RBs) or more.The greatest advantages of the ZC sequence are that the ZC sequence haslow peak-to-average power ratio (PAPR) or low cubic metric andsimultaneously has ideal autocorrelation and low cross-correlationproperties. However, in order to satisfy such properties, the lengths(indicating sounding bandwidth) of necessary sequences should be thesame. Accordingly, in order to support UEs having different soundingbandwidths, allocation to different resource regions is necessary. Inorder to minimize channel estimation performance deterioration,interleaved frequency division multiple access (IFDMA) comb structureshave different sounding bandwidths to support orthogonality of UEs forperforming simultaneous transmission. If such a transmission comb (TC)structure is used in a UE having a small sounding bandwidth, a sequencelength may become less than a minimum sequence length (generally, alength of 24) having orthogonality and thus TC is limited to 2. If thesame TC is used in the same sounding resource, a dimension for providingorthogonality is necessary, thereby leading to use of CDM using cyclicshift.

Meanwhile, there are sequences which have PAPR and correlationperformances slightly lower than those of ZC sequences but are capableof being subjected to resource mapping regardless of sounding bandwidth,such as a Golay sequence and a pseudo random (PN) sequence. In the caseof the Golay sequence, when the autocorrelation values of certainsequences a and b are A_(a) and A_(b), a and b, the sum of theautocorrelation values of which satisfies the following condition, arereferred to as a Golay complementary sequence pair (A_(a)+A_(b)=δ(x)).

For example, when length-26 Golay sequences a and b are a=[1-1 1 1-1-11-1-1-1-1 1-1 1-1-1-1-1 1 1-1-1-1 1-1 1] and b=[-1 1-1-1 1 1-1 1 1 11-1-1-1-1-1-1-1 1 1-1-1-1 1-1 1], the two sequences are concatenated toconfigure a 52-length sequence. In addition, when 0 is mapped to fourresource elements (REs) of both sides, auto-correlation performanceshown in FIG. 7 may be obtained. FIG. 6 is a diagram illustratingperformance of 52-length autocorrelation using two 26-length Golaycomplementary sequence pairs.

FIG. 7 is a diagram illustrating cross-correlation between sequenceshaving different CSs in a 52-length Golay sequence.

A plurality of cyclic shifts (CSs) may be applied to the 52-lengthsequences to generate a plurality of Golay sequences. Cross-correlationbetween Golay sequences having different CSs is shown in FIGS. 8A and8B.

FIGS. 8A and 8B are diagrams illustrating cross-correlation andcubic-metric evaluations of ZC, Golay, and PN sequences.

The cubic metrics (CMs) and cross-correlations of the ZC, Golay, and PNsequences are calculated and compared when TC is 1, 2 or 4. Assumptionsfor evaluation are as follows.

The sounding BW is set to 4, 8, 12, 16, 20, 24, 32, 36, and 48 RBs(based on LTE SRS design).

Like the LTE system, 30-group number u=(f_(gh)(n_(s))+f_(ss))mod 30 isdetermined as follows and (f_(gh)(n_(s))f_(ss)) is determined based on acell ID. In this case, one base sequence v is selected in 4 RBs and twobase sequence numbers v are selected in the others.

In the case of the Golay sequence, a 2048-length truncated binary Golaysequence in an 802.16m system was used and a QPSK PN sequence was usedas an independent bandwidth SRS design example. In this case, in orderto represent 30 groups in the ZC sequence, the Golay sequence wasgenerated using 30 CSs and 30 PN sequences were generated in Matlab.

Evaluation was performed using TC=1, 2, and 4.

In cubic metric evaluation, an oversampling factor (OSF) was set to 8for better resolution.

Referring to FIG. 8A, cross correlation performance was in order ofZC>Golay>PN sequence, and CM performance was in order of ZC>Golay>PN. Inorder to generate an SRS sequence for UL transmission, the ZC sequencehas good performance as in the LTE system. However, in order to increasea degree of freedom in allocation of sounding bandwidth to each UE, theGolay sequence or the PN sequence may not be excluded as SRS sequencecandidates of New RAT.

SRS hopping characteristics in the LTE system are as follows.

SRS hopping operation is performed only at the time of periodic SRStriggering (triggering type 0).

Allocation of SRS resources is given in a predefined hopping pattern.

A hopping pattern may be configured through RRC signaling in aUE-specific manner (however, overlapping is not allowed).

The SRSs may be frequency-hopped and transmitted using a hopping patternfor each subframe in which a cell/UE-specific SRS is transmitted.

The SRS frequency-domain start position and hopping equation areanalyzed through Equation 1 below.

$\begin{matrix}{{k_{0}^{(p)} = {{\overset{¯}{k}}_{0}^{(p)} + {\underset{b = 0}{\sum\limits^{B_{SRS}}}{{`K}_{TC}M_{{sc},b}^{RS}n_{b}}}}}{n_{b} = \left\{ {{\begin{matrix}{{\left\lfloor {4{n_{RRC}/m_{{SRS},b}}} \right\rfloor{mod}\ N_{b}}\ } & {b \leq b_{hop}} \\{{\left\{ {{F_{b}\left( n_{SRS} \right)} + \left\lfloor {4{n_{RRC}/m_{{SRS},b}}} \right\rfloor} \right\}{mod}\ N_{b}}\ } & {otherwise}\end{matrix}{F_{b}\left( n_{SRS} \right)}} = \left\{ {{\begin{matrix}\begin{matrix}{{\left( {N_{b}/2} \right)\left\lfloor \frac{n_{SRS}{{mod}\Pi}_{b^{\prime} = b_{hop}}^{b}N_{b^{\prime}}}{\Pi_{b^{\prime} = b_{hop}}^{b - 1}N_{b^{\prime}}} \right\rfloor} +} \\\left\lfloor \frac{n_{SRS}{{mod}\Pi}_{b^{\prime} = b_{hop}}^{b}N_{b^{\prime}}}{2\Pi_{b^{\prime} = b_{hop}}^{b - 1}N_{b^{\prime}}} \right\rfloor\end{matrix} & {{if}\mspace{14mu} N_{b\;}\mspace{14mu}{even}} \\{\left\lfloor {N_{b}/2} \right\rfloor\left\lfloor {{n_{SRS}/\Pi_{b^{\prime} = b_{hop}}^{b - 1}}N_{b^{\prime}}} \right\rfloor} & {{if}\mspace{14mu} N_{b}\mspace{14mu}{odd}}\end{matrix}n_{SRS}} = \left\{ \begin{matrix}\begin{matrix}{{2N_{SP}n_{f}} + {2\left( {N_{SP} - 1} \right)}} \\{{\left\lfloor \frac{n_{s}}{10} \right\rfloor + \left\lfloor \frac{T_{offset}}{T_{offset\_ max}} \right\rfloor},}\end{matrix} & \begin{matrix}{{{for}\mspace{14mu} 2\mspace{14mu}{ms}\mspace{14mu}{SRS}\mspace{14mu}{periodicity}}\mspace{14mu}} \\{{of}\mspace{14mu}{frame}\mspace{14mu}{structure}\mspace{14mu}{type}\mspace{14mu} 2}\end{matrix} \\{\left. {\left\lfloor {{n_{f} \times 10} + \left\lfloor {n_{s}/2} \right\rfloor} \right)/T_{SRS}} \right\rfloor,} & {otherwise}\end{matrix} \right.} \right.} \right.}} & {{Equation}\mspace{14mu} 1}\end{matrix}$

where, n_(SRS) denotes a hopping interval in the time domain, Nb denotesthe number of branches allocated to a tree level b, and b may bedetermined by setting B_(SRS)in dedicated RRC.

FIG. 9 is a diagram illustrating an LTE hopping pattern(n_(s)=1→n_(s)=4).

An example of configuring an LTE hopping pattern will be described.

LTE hopping pattern parameters may be set through cell-specific RRCsignaling. For example, C_(SRS)=1, N_(RB) ^(UL)=100, n hd f=1, n_(s)=1may be set.

Next, LTE hopping pattern parameters may be set through UE-specific RRCsignaling. For example,

UE A: B_(SRS)=1,b_(hop)=0,n_(RRC)=22,T_(SRS)=10

UE B: B_(SRS)=2,b_(hop)=0,n_(RRC)=10,T_(SRS)=5

UE C: B_(SRS)=3,b_(hop)=2,n_(RRC)=23,T_(SRS)=2

Table 1 below shows agreements about SRS transmission resources in NR

TABLE 1   

 A UE can be configured with an X-port SRS resource, where the SRS   resource spans one or multiple OFDM symbols within a single slot    ✓FFS where all of the X SRS ports are sounded in each OFDM symbol   

 FFS at least for the purposes of CSI acquisition:    ✓ FFS amulti-symbol SRS resource can be configured such that the X     SRSports in each OFDM symbol are transmitted in different     locations ofthe band in different OFDM symbols in the slot in a     frequencyhopping manner     - Note: This allows sounding a larger part of (or thefull) UE     bandwidth using narrower band SRS transmissions     - Note:at any OFDM symbol, all X ports are sounded in the same     portion ofthe band    ✓ Note: Consider UE RF implementation aspects on SRS designthat may     place constraints on the design of the symbol-wise hoppingpattern e.g., Required time for frequency re-tuning (if re-tuningneeded) or transient period if re-tuning is not needed

It has been approved that SRS frequency hopping should be supported inmultiple SRS symbols configured in 3GPP RANI 88 biz, and frequencyhopping between slots in which SRS is configured should be supported.When one multi-symbol SRS is triggered, SRS configuration for full-bandUL resource allocation may be necessary while a certain SRS resourcehops. SRS configuration for full-band UL resource allocation also may benecessary for UL beam management. For example, when multiple SRSs aretriggered for UL beam management of an NR UE, subband-wise UL beammanagement using the same Tx precoding of the NR UE may be necessary.

FIG. 10 is a diagram illustrating multi-symbol SRS triggering for ULbeam management.

Referring to FIG. 10, although UL SRS bandwidth may be configured in onesymbol, multi-symbol SRS may be triggered and configured for the purposeof UL beam management, etc. When the multi-symbol SRS is triggered andthe same Tx precoding is performed in SRS resources (or SRS transmissionresources) which is hopped on each symbol, the UE may provide muchtransmit (Tx) power per SRS symbol. The BS may perform subband selectionthrough a symbol indication after detecting SRS resources per symbol.

Proposal 1

The BS may configure some or all of combinations of SRS sequencegeneration parameters (e.g., transmission comb (TC), TC offset, cyclicshift (CS), and root) for SRS resources, in which frequency hopping isperformed, are changed according to the (frequency) hopping pattern, andthe BS may transmit the configured information to the UE or transmitchanged values of the SRS sequence generation parameter values, whichdesire to be changed, to the UE.

Proposal 1-1

As the detailed proposal of Proposal 1, in Proposal 1-1, SRS sequencegeneration parameters (e.g., TC, TC offset, CS, root, etc.) configuredfor the allocated SRS resource are differently applicable according tothe frequency hopping pattern when frequency hopping is enabled.Additionally, by changing the SRS sequence generation parametersaccording to frequency hopping without additionally increasing dynamicUL downlink control information (DCI) overhead, the BS may determinewhether a specific frequency hopping pattern is properly performed withrespect to the UE after SRS detection.

FIG. 11 is a diagram illustrating a combination{TC(α₁(l′,n_(s))CS(α₁(l′,n_(s)))} of SRS sequence generation parametersaccording to a hopping pattern α₁(l′,n_(s))

Referring to FIG. 11, when the hopping pattern α₁(l′,n_(s)) isconfigured for UE A (where l′ denotes a configured SRS symbol index andn_(s) denotes a configured SRS slot index), a combination of SRSsequence generation parameters corresponding to specific l′, n_(s), andn_(f) (where of is a frame index) may be represented by{TC(α₁(l′,n_(s))),TC_offset(α₁(l′,n_(s))),CS(α₁(l′,n_(s))),root(α₁(l′,n_(s)))}.

Proposal 1-2

The BS transmits a subset of SRS sequence generation parameters amongSRS sequence generation parameters (e.g., TC, TC offset, CS, root, etc.)configured for SRS resources in which frequency hopping (e.g.,intra-slot hopping (or referred to as symbol-level hopping) orinter-slot hopping (or referred to as slot level hopping)) is enabledthrough radio resource control (RRC) signaling of Layer 3 and transmitsthe remaining subset of the SRS generation parameters configured for theallocated SRS resources through downlink control information (DCI) (orDCI format) of Layer 1. The configuration of the subset of the SRSsequence generation parameters is as follows.

The BS transmits the TC, TC offset, and CS values to the UE throughdedicated RRC signaling and transmits the root value to the UE throughDCI. In order for the UE to differently apply the root value accordingto symbol when the multiple symbol SRSs (or may be referred as multiplesymbol SRS resources) are configured in one SRS transmission slot, theBS may transmit the root values corresponding to the number of multiplesymbol SRSs to the UE through DCI or may equally set a root value ofsequences of the multiple symbol SRSs and then transmit one root valueto the UE.

The BS may transmit TC and TC offset through dedicated RRC signaling andtransmit CS and root values through DCI.

The BS may transmit only the TC value through dedicated RRC signalingand transmit TC offset, CS, and root values through DCI.

The BS may transmit only the CS value through dedicated RRC signalingand transmit the remaining subset (e.g., TC, TC offset, and root)through DCI.

The BS may transmit only the root value through dedicated RRC signalingand transmit the remaining subset (e.g., TC, TC offset, and CS) throughDCI.

The BS may transmit various combinations of TC, TC offset, CS, and rootvalues through DCI or RRC signaling.

The UE may generate sequences by variously combining SRS sequencegeneration parameters according to hopping, thereby improving PAPR orlow correlation properties. However, overhead may be increased due toDCI transmission.

FIG. 12 is a diagram illustrating occurrence of collision between UEswhen hopping is performed.

As one embodiment, 1) when the sequence parameter indices in resourcesto be allocated in SRS transmission slot 1 are TC=1, TC offset=0, CS=5,and root=10, the sequence parameter indices in resources to be allocatedin next SRS transmission slot 2 are changed to TC=1, TC offset=0, CS=8,and root=11. In SRS transmission slot 2, CS=8 and root=11 may betransmitted through DCI or inferred by a hopping pattern.

As another embodiment, when a truncated ZC SRS sequence is used,different resources in SRS transmission slot 1 are allocated to UE 1 andUE 2. However, in next SRS transmission slot 2, resources of UE 1 and UE2 overlap in terms of a specific SRS symbol index and CS=3 of UE 1 andCS=3 of UE 2 are applied and thus the BS changes CS=3 of UE 2 to CS=5 ofUE 2, thereby maintaining low-correlation properties.

Proposal 1-3

As a combination of sequence generation parameters (e.g. TC, TC offset,CS, and root) configured for SRS resources in which frequency hopping(e.g., intra-slot hopping, inter-slot hopping, etc.) is enabled, inorder to reduce DCI signaling overhead, the BS may transmit a specificset to the UE through RRC signaling and transmit DCI including a requestfield to the UE and the UE may acquire information on a sequencecombination corresponding to SRS resources which hopping is performed.As one embodiment, Table 2 below shows a set of sequence generationparameters transmitted by the BS through the DCI. It has been approvedthat SRS frequency hopping should be supported in multiple SRS symbolsconfigured in 3GPP RANI 88 biz, and frequency hopping between slots inwhich SRS is configured should be supported. When one multi-symbol SRSis triggered, SRS configuration for full-band UL resource allocation maybe necessary while a certain SRS resource hops. SRS configuration forfull-band UL resource allocation also may be necessary for UL beammanagement. For example, when multiple SRSs are triggered for UL beammanagement of an NR UE, subband-wise UL beam management using the sameTx precoding of the NR UE may be necessary.

FIG. 10 is a diagram illustrating multi-symbol SRS triggering for ULbeam management.

Referring to FIG. 10, although UL SRS bandwidth may be configured in onesymbol, multi-symbol SRS may be triggered and configured for the purposeof UL beam management, etc. When the multi-symbol SRS is triggered andthe same Tx precoding is performed in SRS resources (or SRS transmissionresources) which is hopped on each symbol, the UE may provide muchtransmit (Tx) power per SRS symbol. The BS may perform subband selectionthrough a symbol indication after detecting SRS resources per symbol.

Proposal 1

The BS may configure some or all of combinations of SRS sequencegeneration parameters (e.g., transmission comb (TC), TC offset, cyclicshift (CS), and root) for SRS resources, in which frequency hopping isperformed, are changed according to the (frequency) hopping pattern, andthe BS may transmit the configured information to the UE or transmitchanged values of the SRS sequence generation parameter values, whichdesire to be changed, to the UE.

Proposal 1-1

As the detailed proposal of Proposal 1, in Proposal 1-1, SRS sequencegeneration parameters (e.g., TC, TC offset, CS, root, etc.) configuredfor the allocated SRS resource are differently applicable according tothe frequency hopping pattern when frequency hopping is enabled.Additionally, by changing the SRS sequence generation parametersaccording to frequency hopping without additionally increasing dynamicUL downlink control information (DCI) overhead, the BS may determinewhether a specific frequency hopping pattern is properly performed withrespect to the UE after SRS detection.

FIG. 11 is a diagram illustrating a combination{TC(α₁(l′,n_(s))CS(α₁(l′,n_(s)))} of SRS sequence generation parametersaccording to a hopping pattern α₁(l′,n_(s)).

Referring to FIG. 11, when the hopping pattern α₁(l′,n_(s)) isconfigured for UE A (where l′ denotes a configured SRS symbol index andn_(s) denotes a configured SRS slot index), a combination of SRSsequence generation parameters corresponding to specific l′, n_(s), andn_(f) (where of is a frame index) may be represented by{TC(α₁(l′,n_(s))),TC_offset(α₁(l′,n_(s))),CS(α₁(l′,n_(s))),root(α₁(l′,n_(s)))}.

Proposal 1-2

The BS transmits a subset of SRS sequence generation parameters amongSRS sequence generation parameters (e.g., TC, TC offset, CS, root, etc.)configured for SRS resources in which frequency hopping (e.g.,intra-slot hopping (or referred to as symbol-level hopping) orinter-slot hopping (or referred to as slot level hopping)) is enabledthrough radio resource control (RRC) signaling of Layer 3 and transmitsthe remaining subset of the SRS generation parameters configured for theallocated SRS resources through downlink control information (DCI) (orDCI format) of Layer 1. The configuration of the subset of the SRSsequence generation parameters is as follows.

The BS transmits the TC, TC offset, and CS values to the UE throughdedicated RRC signaling and transmits the root value to the UE throughDCI. In order for the UE to differently apply the root value accordingto symbol when the multiple symbol SRSs (or may be referred as multiplesymbol SRS resources) are configured in one SRS transmission slot, theBS may transmit the root values corresponding to the number of multiplesymbol SRSs to the UE through DCI or may equally set a root value ofsequences of the multiple symbol SRSs and then transmit one root valueto the UE.

The BS may transmit the TC and TC offset through dedicated RRC signalingand transmit CS and root values through DCI.

The BS may transmit only the TC value through dedicated RRC signalingand transmit TC offset, CS, and root values through DCI.

The BS may transmit only the CS value through dedicated RRC signalingand transmit the remaining subset (e.g., TC, TC offset, and root)through DCI.

The BS may transmit only the root value through dedicated RRC signalingand transmit the remaining subset (e.g., TC, TC offset, and CS) throughDCI.

The BS may transmit various combinations of TC, TC offset, CS, and rootvalues through DCI or RRC signaling.

The UE may generate sequences by variously combining SRS sequencegeneration parameters according to hopping, thereby improving PAPR orlow correlation properties. However, overhead may be increased due toDCI transmission.

FIG. 12 is a diagram illustrating occurrence of collision between UEswhen hopping is performed.

As one embodiment, 1) when the sequence parameter indices in resourcesto be allocated in SRS transmission slot 1 are TC=1, TC offset=0, CS=5,and root=10, the sequence parameter indices in resources to be allocatedin next SRS transmission slot 2 are changed to TC=1, TC offset=0, CS=8,and root=11. In SRS transmission slot 2, CS=8 and root=11 may betransmitted through DCI or inferred by a hopping pattern.

As another embodiment, when a truncated ZC SRS sequence is used,different resources in SRS transmission slot 1 are allocated to UE 1 andUE 2. However, in next SRS transmission slot 2, resources of UE 1 and UE2 overlap in terms of a specific SRS symbol index and CS=3 of UE 1 andCS=3 of UE 2 are applied and thus the BS changes CS=3 of UE 2 to CS=5 ofUE 2, thereby maintaining low-correlation properties.

Proposal 1-3

As a combination of sequence generation parameters (e.g. TC, TC offset,CS, and root) configured for SRS resources in which frequency hopping(e.g., intra-slot hopping, inter-slot hopping, etc.) is enabled, inorder to reduce DCI signaling overhead, the BS may transmit a specificset to the UE through RRC signaling and transmit DCI including a requestfield to the UE and the UE may acquire information on a sequencecombination corresponding to SRS resources which hopping is performed.As one embodiment, Table 2 below shows a set of sequence generationparameters transmitted by the BS through the DCI.

TABLE 2 Sequence request field (symbol- level hopping) ‘00’ ‘01’ ‘10’‘11’ Combination TC = 2, TC TC = 2, TC TC = 4, TC TC = 4, TC of sequenceoffset = 0, offset = 1, offset = 0, offset = 3, generation CS = 4, CS =8, CS = 11, CS = 7, parameters root = 10 root = 11 root = 2 root = 3

Upon receiving the request field for the sequence generation parametersin an SRS allocation resource (e.g., slot) indicating “01” through DCI,the UE may generate a sequence for SRS transmission in the correspondingresource (e.g., corresponding slot) using TC=2, TC offset=1, CS=8, androot=11. When the number of multiple SRS symbols in the SRS slot is 2,the UE may continuously receive the request fields of “00” and “10” fromthe BS. In this case, the UE may generate the SRS sequence in a firstSRS symbol using TC=2, TC offset=0, CS=4, and root=10 and generate theSRS sequence in a second SRS symbol using TC=4, TC offset=0, CS=11, androot=2. Alternatively, when the request field indicates “10”, the UE maygenerate the same SRS sequence in two symbols using TC=4, TC offset=0,CS=11, and root=2.

Proposal 1-4

The BS may configure that sequence generation parameters (e.g., TC, TCoffset, CS, and root values) configured for SRS resource, in whichfrequency hopping (e.g., intra-slot hopping or inter-slot hopping) isenabled, are not changed when frequency hopping is performed. It may bedesirable when hopping is performed with the most general sequencegeneration parameter configuration, that an overlapped frequency regionin a specific SRS instance be avoided or a hopping pattern be generatedsuch that low correlation is achieved in the overlapping frequencyregion.

Proposal 2

A frequency hopping configuration method may be divided into a slotlevel frequency hopping configuration (inter-slot hopping configuration)and a symbol-level frequency hopping configuration (intra-slot hoppingconfiguration).

Parameters for Inter-Slot Hopping Configuration

When the parameters for inter-slot hopping configuration include SRSresource position information: the parameters for inter-slot hoppingconfiguration may include a value indicating an SRS resource allocationband and SRS resource allocation position in each slot (e.g., an SRSallocation start RE value, an SRS allocation start RB value, an SRSallocation end RE value, and an SRS allocation end RB value for aspecific UE, and a value indicating an SRS transmission range and afrequency position of each slot (e.g., a resource indication value(RIV)), a subband index applied within one slot, and a partial bandindex applied within one slot), an inter-slot hopping cycle, aninter-slot hopping enable flag, etc.

When the hopping pattern is used: the parameters for inter-slot hoppingconfiguration may include an inter-slot hopping cycle, an inter-slothopping enable flag, and an inter-slot hopping pattern.

Parameters for Intra-Slot Hopping Configuration

When the parameters for intra-slot hopping configuration include SRSresource position information: the parameters for intra-slot hoppingconfiguration may include a value indicating the SRS resource allocationposition in each symbol (e.g., an RIV, an RE/RB index, a subband index,and a partial band index), the number of configured SRS symbols in theSRS transmission slot and an index, an intra-slot hopping cycle, anintra-slot hopping enable flag, etc.

When the hopping pattern is used: the parameters for intra-slot hoppingconfiguration may include the number of configured SRS symbols in theSRS transmission slot and an index, an intra-slot hopping cycle, anintra-slot hopping pattern, an intra-slot hopping enable flag, etc. TheBS may transmit such parameters to the UE according to the followingconfiguration.

Hopping configuration may be two combinations of intra-slot/inter-slothopping and the hopping cycle may be defined as follows. The intra-slothopping cycle may be defined as the number of SRS symbols until an SRSresource allocated according to the number of SRS symbols in a given SRSslot hops on each symbol and returns to an original SRS frequencyposition. The inter-slot hopping cycle may be defined as the number ofSRS slots until the SRS resource hops on each SRS slot and returns to anoriginal SRS frequency position.

Proposal 2-1

In the case of a periodic/semipersistent SRS, the BS may transmit theparameters for intra-slot hopping configuration to the UE throughdedicated RRC signaling and transmit the parameters for inter-slothopping configuration to the UE through DCI for an SRS transmissionslot. DCI signaling overhead is increased in each SRS transmission slot,but inter-slot hopping information may be dynamically acquired toflexibly configure inter-slot hopping. As an embodiment, an example oftransmitting the parameters for intra-slot hopping through RRC signalingand transmitting the parameters for inter-slot hopping configurationthrough DCI when periodic/semipersistent SRS triggering is performedwill be illustrated.

FIG. 13 illustrates an example of transmitting intra-slot hoppingparameters through RRC signaling and transmitting inter-slot hoppingparameters through DCI signaling.

Referring to FIG. 13, as an example of (dedicated) RRC signaling forintra-slot hopping configuration, the following information istransmitted through (dedicated) RRC signaling: the SRS configuration(allocation) start RB index=1, the SRS configuration (allocation) end RBindex=17, the SRS BW=16 RBs, the number of configured SRS symbols in theSRS transmission slot=4, the start symbol position index of theconfigured SRS=8, the end symbol position index of the configuredSRS=11, the partial band index=1, and the symbol hopping cycle=4symbols.

Referring to FIG. 13, as an example of DCI signaling for inter-slothopping configuration, the following information is transmitted throughDCI signaling.

The DCI for the first SRS slot may indicate the SRS start RB index=1,the SRS end RB index=65, the partial band index=1, the inter-slothopping cycle: 2 SRS slots, etc.

The DCI for the second SRS slot may indicate the SRS allocation start RBindex=65, the SRS allocation end RB index=129, the partial band index=1,the inter-slot hopping cycle: 2 SRS slots, etc.

The inter-slot/intra-slot hopping pattern may be understood by thefollowing example. In NR, when the number of slots in one frame n_(f) isN_(s), the index of each slot is expressed as n_(s), l′ is the symbolindex of the configured SRS, and T_(SRS) is an SRS transmission cycle,n_(SRS) for hopping may be configured as shown in Equation 2 below.

$\begin{matrix}{{n_{SRS} = l^{\prime}},{k_{0}^{(p)} = {{\overset{¯}{k}}_{0}^{(p)} + {F\left( {i_{sb},n_{f},n_{s},T_{SRS}} \right)} + {\sum\limits_{b = 0}^{B_{SRS}}{{`K}_{TC}M_{{sc},b}^{RS}n_{b}}}}},} & {{Equation}\mspace{14mu} 2}\end{matrix}$

where, F(i_(sb),n_(f),n_(s),T_(SRS)) is an intra-slot hopping positionfunction according to a subband index i_(sb). B_(SRS) spans on one SRSsubband. F(i_(sb),n_(f),n_(s),T_(SRS))=(i_(sb)(n_(f),n_(s),T_(SRS))−1)×BW_(sb) and BW^(sb)is the number of REs indicating the bandwidth of the subband.i_(sb)(n_(f),n_(s),T_(SRS))=c(n_(f),n_(s),T_(SRS))mod I_(sb) and I_(sb)is a total number of subbands. c( ) is a scrambling function.

FIG. 13 shows an example in which, after hopping is performed in alocalized frequency region, hopping configuration in another localizedfrequency region is enabled in a next SRS transmission slot. In a UEhaving a narrow band RF, it is advantageous to perform hopping in alocalized frequency region and to perform hopping in another localizedfrequency region in the next slot in consideration of retuning delay.

As another example, when periodic SRS triggering occurs, the BS maytransmit parameters for intra-slot hopping through RRC signaling andtransmit parameters for inter-slot hopping configuration through DCIsignaling.

FIG. 14 is a diagram illustrating the case in which a BS transmitsintra-slot hopping parameters through DCI signaling and transmitsinter-slot hopping parameters through RRC signaling.

Example of Transmission of DCI for Inter-Slot Hopping Configuration

The BS may indicate the SRS subband index (1 to 64 RBs)=1, the partialband index=1, and the inter-slot hopping cycle=2 SRS slots, in DCI forthe first SRS slot. The BS may indicate the SRS subband index (1 to 64RBs)=2, the partial band index=1, and the inter-slot hopping cycle=2 SRSslots, in DCI for the second SRS slot.

Proposal 2-1-2

In the case of a periodic SRS and/or semipersistent SRS, the BS maytransmit parameters for inter-slot hopping configuration to the UEthrough (dedicated) RRC signaling and transmit parameters for intra-slothopping configuration to the UE through DCI for an SRS transmissionslot.

This may be considered when intra-slot hopping is flexibly applied in afixed inter-slot hopping pattern. However, parameter transmissionoverhead for intra-slot hopping is increased.

FIG. 15 illustrates the case where a BS transmits intra-slot hoppingparameters through RRC signaling and transmits inter-slot hoppingparameters through DCI according to Proposal 2-1-2.

As one embodiment, at the time of periodic/semipersistent SRStransmission, the BS may transmit parameters for inter-slot hoppingconfiguration through RRC signaling and transmit parameters forintra-slot hopping configuration through DCI (when the SRS resourceposition of each symbol is designated). Hereinafter, this will bedescribed with reference to FIG. 15.

Example of transmission of (dedicated) RRC signaling for inter-slothopping configuration: The (dedicated) RRC signaling for inter-slothopping configuration may indicate the SRS allocation start RB index=1,the SRS allocation end RB index=129 RBs, the partial band index=1, andthe inter-slot hopping cycle=2 SRS slots.

Example of transmission of DCI for intra-slot hopping configuration

The DCI for the first SRS slot may indicate the SRS BW=16 RBs, thenumber of configured SRS symbols in the SRS transmission slot=4, thestart symbol position of the configured SRS=8, the allocation end symbolposition of the configured SRS=11, the partial band index=1, and thesymbol hopping cycle=4 symbols. As shown in FIG. 15, the DCI for thefirst SRS slot indicates the first symbol SRS start RB index=1, thefirst symbol SRS end RB index=17, the second symbol SRS start RBindex=17, the second symbol SRS end RB index =33, the third symbol SRSstart RB index=33, the third symbol SRS end RB index=49, the fourthsymbol SRS start RB index=49, and the fourth symbol SRS end RB index=65.

The DCI for the second SRS slot may indicate the SRS BW=32 RBs, thenumber of configured SRS symbols in the SRS transmission slot=2, thestart symbol position of the configured SRS=8, the end symbol positionof the configured SRS=9, partial band index=1, and the symbol hoppingcycle=2 symbols. As shown in FIG. 15, the DCI for the first SRS slotindicates the 1^(st) symbol SRS start RB index=65, the first symbol SRSend RB index=97, the second symbol SRS allocation start RB index=97, andthe second symbol SRS allocation end RB index=129.

As another embodiment, at the time of periodic SRS transmission, the BSmay transmit parameters for inter-slot hopping configuration through RRCsignaling and transmit parameters for intra-slot hopping configurationthrough DCI (however, the SRS resource position of each symbol isdetermined by the intra-slot hopping pattern).

The (dedicated) RRC signaling for inter-slot hopping configuration mayindicate the SRS allocation start RB index=1, the SRS allocation end RBindex=129, partial band index =1, and the inter-slot hopping cycle=2 SRSslots.

The (dedicated) RRC signaling for intra-slot hopping configuration mayindicate the SRS BW=16 RBs, the number of configured SRS symbols in theSRS transmission slot=4, the start symbol position of the configuredSRS=8, the end symbol position of the configured SRS=11, the partialband index=1, the subband index in a partial band=1, and the symbolhopping cycle=4 symbols. The DCI for the second SRS slot may indicatethe SRS BW=32 RBs, the number of configured SRS symbols in the SRStransmission slot=2, the start symbol position of the configured SRS=8,the end symbol position of the configured SRS=9, the partial bandindex=1, the subband index in a partial band=2, and the symbol hoppingcycle=2 symbols.

Proposal 2-1-3

In the case of periodic/semipersistent SRS, the BS may transmitparameters for inter-slot frequency hopping configuration and parametersfor intra-slot hopping configuration to the UE through (dedicated) RRCsignaling. The configuration of Proposal 2-1-3 has smallest overhead forfrequency hopping. When applying intra-slot hopping and inter-slothopping, hopping is regularly performed according to hopping pattern.

FIG. 16 is a diagram illustrating an example of transmitting parametersfor intra-slot hopping configuration and parameters for inter-slothopping configuration through RRC signaling according to Proposal 2-1-3.

Example of (Dedicated) RRC for Inter-Slot Hopping Configuration

Dedicated RRC signaling for inter-slot hopping configuration mayindicate the SRS allocation start RB index=1, the SRS allocation end RBindex=129, the partial band index=1, and the inter-slot hopping cycle=2SRS slots.

Example of (Dedicated) RRC for Intra-Slot Hopping Configuration

Dedicated RRC signaling for intra-slot hopping configuration mayindicate the SRS allocation start RB index=1, the SRS allocation end RBindex=17, the SRS BW=16 RBs, the number of configured SRS symbols in theSRS transmission slot=4, the start symbol position of the configuredSRS=8, the end symbol position of the configured SRS=11, the partialband index=1, and the symbol hopping cycle=4 symbols.

Proposal 2-1-4

In the case of periodic/semipersistent SRS, the BS may transmitparameters for inter-slot hopping configuration and parameters forintra-slot hopping configuration through (dedicated) RRC and maytransmit some parameters through DCI for hopping information of the SRStransmission slot. By acquiring dynamic information of specificparameters, flexible configuration may be enabled at the time ofhopping. In this case, overhead is not large.

Example of Transmission of DCI of Some Hopping Parameters

Dedicated RRC signaling for inter-slot hopping configuration mayindicate the SRS allocation start RB index=1, the SRS allocation end RBindex=129, the partial band index=1, and the inter-slot hopping cycle=2SRS slots. Dedicated RRC signaling for intra-slot hopping configurationmay indicate the SRS BW=16 RBs, the number of configured SRS symbols inthe SRS transmission slot=4, the start symbol position of the configuredSRS=8, the end symbol position of the configured SRS=11, the partialband index=1, and the symbol hopping cycle =4 symbols.

DCI for Intra-Slot Hopping Configuration

The DCI for the first SRS slot may indicate the SRS subband index (1 to64 RBs)=1. The DCI for the second SRS slot may indicate the SRS subbandindex (1 to 64 RBs)=2.

Proposal 2-1-5

In the case of periodic/semipersistent SRS, during the hopping cycle(from when hopping is performed in a hopping start resource to whenreturning to the position of the hopping start resource), a parameter(e.g., a hopping offset value) for differentiating an inter-symbolhopping pattern at the time of next hopping is defined. This parametermay be transmitted through DCI or RRC signaling.

The hopping offset according to Proposal 2-1-5 may differentiate thehopping pattern at a predetermined time, thereby dispersing interferenceoccurring at the time of hopping. As an embodiment, a parameter fordifferentiating the hopping pattern according to the hopping cycle isapplicable.

FIG. 17 is a diagram illustrating an example of applying differentintra-slot hopping patterns for each hopping cycle.

When considering a parameter h_(shift) for changing the intra-slothopping pattern for each hopping cycle, the BS may transmit h_(shift) tothe UE through DCI every hopping cycle or h_(shift) is expressedaccording to T_(hopping) in Equation 3, such that hopping is performedwith the intra-slot hopping pattern other than the intra-slot hoppingpattern used in a previous hopping cycle as shown in FIG. 15.

When hopping cycle T_(hopping)=4 slot , Equation 3 below is obtained.

n _(SRS)=(l′+h _(shift))mod L′, h _(shift)=└(n _(f) ×N _(s) +n _(s))/T_(hopping)┘  Equation 3

where, L′ denotes the number of symbols of the SRS allocated to one SRSslot.

T_(hopping) may be expressed using the length of an SRS resourceallocated to one symbol, a UL BW length, T_(SRS), and L′. That is,

$T_{hopping} = {\frac{B{W_{UL}/{BW}_{SRS}}}{L^{\prime}} \times T_{SRS}}$

Proposal 2-2-1

In the case of aperiodic SRS, the BS may configure parameters forinter-slot hopping configuration and parameters for intra-slot hoppingconfiguration and transmit the parameters to the UE through (dedicated)RRC or MAC-CE. When the BS transmits through MAC-CE, a valid period (orinterval) of the hopping parameters transmitted through the MAC-CE isdetermined using an activation signal, a deactivation signal, or atimer. Hopping may be performed whenever the SRS is dynamicallytriggered with a pre-defined intra-slot/inter-slot hopping pattern. Inthis case, overhead is also small.

FIG. 18 is a diagram illustrating an example of applying the sameintra-slot hopping pattern at the time of aperiodic SRS transmission.

Parameters for inter-slot hopping configuration and parameters forintra-slot hopping configuration may be configured/transmitted throughRRC signaling (hopping in a specific subband is applied).

(Dedicated) RRC signaling for inter-slot hopping configuration mayindicate the SRS allocation start RB index=1, the SRS allocation end RBindex=129, the subband index=1, and the partial band index=1.(Dedicated) RRC signaling for intra-slot hopping configuration mayindicate the SRS BW=16 RBs, the number of configured SRS symbols in theSRS transmission slot=4, the configured SRS start symbol position=8, theconfigured SRS end symbol position=11, the subband index=1, the partialband index=1, and the symbol hopping cycle=4 symbols.

As shown in FIG. 18, parameters for inter-slot hopping configuration andparameters for intra-slot hopping configuration areconfigured/transmitted through RRC signaling, and the aperiodic SRS istriggered in SRS slot 1, SRS slot 5 and SRS slot 12. If n_(SRS)=α₁(l′),n_(SRS)=α₁(l ′), and n_(SRS)=α₁(l′) are configured, the symbol hoppingpattern may be equally applied.

FIG. 19 is a diagram illustrating applying different intra-slot hoppingpatterns at the time of aperiodic SRS transmission.

If n_(SRS)=α₁(l′,1), n_(SRS)=α₁(l′,5), and n_(SRS)=α₁(l′,12) areconfigured, as shown in FIG. 19, different intra-slot patterns mayappear per slot. As another embodiment, the BS may configure/transmitparameters for inter-slot hopping configuration and parameters forintra-slot hopping configuration through RRC signaling (hopping in apartial band is applied).

FIG. 20 is a diagram illustrating an example of applying differentintra-slot hopping patterns (hopping over a partial band) at the time ofaperiodic SRS transmission.

(Dedicated) RRC signaling for inter-slot hopping configuration mayindicate the SRS allocation start RB index=1, the SRS allocation end RBindex=129, and the partial band index=1. (Dedicated) RRC signaling forintra-slot hopping configuration may indicate the SRS BW=32RBs, thenumber of configured SRS symbols in the SRS transmission slot=4, thestart symbol position of the configured SRS=8, the end symbol positionof the configured SRS=11, the partial band index=1, and the symbolhopping cycle=4 symbols.

As shown in FIG. 20, parameters for inter-slot hopping configuration andparameters for intra-slot hopping configuration areconfigured/transmitted through RRC signaling and the aperiodic SRS istriggered in SRS slot 1, SRS slot 5, and SRS slot 12. Ifn_(SRS)=αa₁(l′,1), n_(SRS)=α₁(l′,5) and n_(SRS)=α₁(l′,12) areconfigured, different intra-slot patterns may appear per slot.

Proposal 2-2-2

In the case of the aperiodic SRS, the BS may configure/transmitparameters for inter-slot hopping configuration through (dedicated) RRCsignaling and configure/transmit parameters for intra-slot hoppingconfiguration through DCI when the SRS is triggered. In contrast, the BSmay configure/transmit parameters for inter-slot hopping configurationthrough DCI whenever the SRS is triggered and configure/transmitparameters for intra-slot hopping configuration through (dedicated) RRCsignaling.

The BS may dynamically provide information on parameters for intra-slothopping and inter-slot hopping to the UE whenever the SRS is triggered.Of course, in this case, signaling overhead of the BS may be increased.

FIG. 21 is a diagram illustrating an example of applying differentintra-slot hopping patterns (hopping over a specific subband) at thetime of aperiodic SRS transmission. As an embodiment, in the case of theaperiodic SRS, the BS may configure/transmit parameters for inter-slothopping configuration through (dedicated) RRC signaling and transmitparameters for intra-slot hopping configuration through DCI. In FIG. 21,the SRS is aperiodically triggered when the SRS slot positions areindices of 1, 5, and 12. The BS may transmit the following informationto the UE when indicating that the aperiodic SRS is triggered.(Dedicated) RRC signaling for inter-slot hopping configuration mayindicate the SRS allocation start RB index=1, the SRS allocation end RBindex=129, and the partial band index=1.

As an example of transmission of DCI for intra-slot hoppingconfiguration, the DCI for SRS slot 1 may indicate the SRS BW=16 RBs,the number of configured SRS symbols in the SRS transmission slot=4, thestart symbol position of the configured SRS=8, the end symbol positionof the configured SRS=11, the partial band index=1, the subband index ina partial band=1, and the symbol hopping cycle=4 symbols. The DCI forSRS slot 5 may indicate the SRS BW=32 RBs, the number of configured SRSsymbols in the SRS transmission slot=2, the start symbol position of theconfigured SRS=8, the end symbol position of the configured SRS=9, thepartial band index=1, the subband index in a partial band=2, and thesymbol hopping cycle=2 symbols. The DCI for SRS slot 12 may indicate theSRS BW=16 RBs, the number of configured SRS symbols in the SRStransmission slot=4, the start symbol position of the configured SRS=8,the end symbol position of the configured SRS=11, the partial bandindex=1, the subband index in a partial band=1, and the symbol hoppingcycle=4 symbols. At this time, if a value indicating the intra-slotpattern is n_(SRS)=α₁(l′,1), n_(SRS)=α₁(l′,5) and n_(SRS)=α₁(l′,12),different intra-slot patterns may be configured per slot.

Proposal 2-2-3

In the case of aperiodic SRS, the BS may configure/transmit informationon a specific set of parameters for inter-slot hopping configurationand/or parameters for intra-slot hopping configuration to the UE throughRRC signaling or DCI including the request field. In this case,signaling overhead may be significantly reduced.

FIG. 22 is a diagram illustrating SRS transmission according to requestfield transmission using a hopping parameter set at the time ofaperiodic SRS transmission.

Table 4 below shows an intra-slot hopping configuration parameter setaccording to Proposal 2-2-3.

TABLE 4 Request field (in the case of symbol- level hopping) ‘00’ ‘01’‘10’ ‘11’ Parameter SRS BW = SRS BW = SRS BW = SRS BW = values for 16RBs 16 RBs 16 RBs 16 RBs intra-slot Number of Number of Number of Numberof hopping con- symbols of symbols of symbols of symbols of figurationconfigured configured configured configured SRS in SRS SRS in SRS SRS inSRS SRS in SRS transmission transmission transmission transmission slot= 4 slot = 4 slot = 2 slot = 2 configured configured configuredconfigured SRS start SRS start SRS start SRS start symbol symbol symbolsymbol position = 8 position = 8 position = 8 position = 10 configuredconfigured configured configured SRS end SRS end SRS end SRS end symbolsymbol symbol symbol position = 11 position = 11 position = 9 position =11 partial band partial band partial band partial band index = 1 index =1 index = 1 index = 1 subband subband subband subband index in index inindex in index in a partial a partial a partial a partial band = 1 band= 2 band = 1 band = 2 symbol symbol symbol symbol hopping hoppinghopping hopping cycle = 4 cycle = 4 cycle = 2 cycle = 2 symbols symbolssymbols symbols

As shown in FIG. 22, the periodic SRS is triggered in slot indexes whichSRS slot positions are 1, 5 and 12. FIG. 22 shows that the BS transmitsDCI to the UE. It is illustrated that DCI indicates the request fieldfor SRS slot 1 of “00”, DCI indicates the request field for SRS slot 5of “01”, and DCI indicates the request field for SRS slot 12 of “11”from the BS to the UE.

Proposal 2-2-4

In the case of the aperiodic SRS, the BS may configure/transmit a set ofan inter-slot hopping pattern through RRC signaling, and the BS maytransmit an intra-slot hopping request field through DCI when multipleaperiodic SRS symbols are triggered. When the SRS is triggered,different hopping patterns may be flexibly configured between multipleSRS symbols. Table 5 below shows the symbol-level hopping request field.

TABLE 5 Intra-slot hopping request field ‘00’ ‘01’ ‘10’ ‘11’ Hoppingpattern F(0, n_(f), n_(s), T_(SRS)) F(1, n_(f), n_(s), T_(SRS)) F(2,n_(f), n_(s), T_(SRS)) F(3, n_(f), n_(s), T_(SRS)) function F(i_(sb),n_(f), n_(s), T_(SRS))

Proposal 2-2-5

The BS may configure/transmit a set indicating a combination of anintra-slot hopping pattern set (e.g., the hopping request fields ‘00’,‘01’, ‘10’ and ‘11’ shown in Table 13) and a sequence parameter set(e.g., TC, TC offset, CS, root, etc.) through RRC signaling and transmitone or a plurality of request fields to be applied to a slot in which anSRS is triggered, through UL DCI. For example, Table 6 shows the requestfield of the sequence parameter set (e.g., TC, TC offset, CS, root,etc.) and the hopping parameter set.

TABLE 6 Request field ‘00’ ‘01’ ‘10’ ‘11’ Hopping pattern F(0, n_(f),n_(s), T_(SRS)) F(1, n_(f), n_(s), T_(SRS)) F(2, n_(f), n_(s), T_(SRS))F(3, n_(f), n_(s), T_(SRS)) function F(i_(sb), n_(f), n_(s), T_(SRS))Sequence parameter 0 1 2 3 set index

The UE may select a hopping pattern and sequence parameter set indicatedby the request field received through DCI, generate an SRS sequence, andtransmit an SRS.

Proposal 2-2-6

When multiple aperiodic SRS symbols are triggered, a triggering counterN is introduced. The BS may configure/transmit the triggering counter Nthrough DCI or RRC signaling.

FIG. 23 is a diagram illustrating hopping when a triggering counter N=3.

In F(i_(pb)(n mod N),n_(f),n_(s),T_(SRS)), n may indicate the number oftimes of triggering the aperiodic multiple SRS symbols starting from areference UL slot.

Proposal 2-3

In the case of a semipersistent SRS, for intra-slot hopping and/orinter-slot hopping, the BS may configure/transmit parameters foroperations of performing hopping and finishing hopping (e.g., an SRStriggered slot index in which slot/symbol-level hopping starts,semipersistent frequency hopping activation, an SRS triggered slot indexin which slot/symbol-level hopping ends, and semipersistent frequencyhopping deactivation) to the UE through DCI or MAC-CE. A timer forhopping deactivation may operate at the time of activation.

When the semipersistent SRS is activated and hopping is activated,parameters for hopping configuration become valid and, when hopping isdeactivated, parameters for hopping configuration do not become valid.

Proposal 2-4

For a UE located at a cell edge in order to acquire SRS receive power,the BS may define the repetition number of SRS symbols, allocate SRSresources at the same position until the repetition number, andconfigure the UE to perform hopping in a next SRS symbol or a next SRSslot. In this case, the BS may transmit information on the repetitionnumber of SRS symbols to the UE through RRC signaling or UL DCI.Accordingly, the reception side (the BS) may combine the SRS symbolsallocated to the same frequency resources by the repetition number.

FIG. 24 is a diagram illustrating symbol-level hopping when a repetitionnumber is 2 (r=2).

As shown in FIG. 24, when the repetition number of symbols is 2 (r=2),L′=4 , and T_(hopping)=2T_(SRS), in the case of the periodic SRS,

$n_{SRS} = {\left\lfloor {l^{\prime}/r} \right\rfloor + {\frac{N_{{SRS\_ symbo}l}}{r} \times \left\lfloor {\left( {{n_{f} \times N_{s}} + n_{s}} \right)/T_{SRS}} \right\rfloor}}$

may be expressed. N_(SRS_symbol) is the configured number of SRS symbolsin the configured SRS slot. In the case of an aperiodic SRS, since onlyconfiguration in one slot may be necessary, n_(SRS)=└l′/r┘ may beexpressed.

Proposal 2-4-1

The UE located at the cell edge may perform UL full-band transmission inmultiple symbols configured to acquire SRS receive power. In this case,sequence parameters, precoding vectors mapped to the SRS resources, andports may be equally applied.

Proposal 2-5

It is possible to support SRS hopping through a single hoppingconfiguration integrating intra-slot configuration and/or inter-slothopping configuration. At this time, the parameters may be as follows.

When information on the parameters for the single hopping configurationincludes SRS resource position information: The information on theparameters for the single hopping configuration may include informationon a value indicating the SRS resource allocation position in eachsymbol starting from a hopping enable symbol (e.g., MV, RE/RB index,subband index, and partial band index), the number of configured SRSsymbols in the SRS transmission slot and index, the intra-slot hoppingcycle, the inter-slot hopping cycle, a hopping enable flag indicatingwhether hopping is enabled, etc.

When the hopping pattern is used, the information on the parameters forthe single hopping configuration may include the number of configuredSRS symbols in the SRS transmission slot and the index, the symbol-levelhopping cycle, the slot-level hopping cycle, the intra-slot and/orinter-slot hopping pattern, the hopping enable flag, etc.

FIG. 25 is a diagram illustrating a hopping pattern according to thenumber of SRS symbols.

As an embodiment, the case of using the hopping pattern will bedescribed.

Example of (dedicated) RRC signaling for frequency hopping configuration

(Dedicated) RRC signaling for frequency hopping configuration mayinclude the SRS BW=32 RBs, the number of configured SRS symbols in theSRS transmission slot (N_(SRS_symbol))=4, the start symbol position (orthe index) of the configured SRS=8, the end symbol position (or theindex) of the configured SRS=11, the partial band index=1, the symbolhopping cycle T_(symbol_hopping)=3 symbols, and the slot hopping cycleT_(slot_hopping)=T_(SRS) slots. Whenn_(SRS)=└(l′+N_(SRS_symbol)×└(n_(f)×N_(s)+n_(s))/T_(SRS)┘)modT_(symbol_hopping)┘ is configured (here, n_(SRS) is a hopping intervalin the time domain), as shown in FIG. 25, the hopping pattern may not bechanged according to SRS slot but may be formed according to the numberof the SRS symbols.

FIG. 26 is a diagram illustrating a hopping pattern according to thenumber of SRS symbols (when the number of symbols of the SRS in an SRSslot is less than a symbol hopping cycle).

As another embodiment, the case of using the hopping pattern will bedescribed. In the example of FIG. 25, hopping is easily applicable evenwhen the number of symbols in one SRS

slot is less than the symbol hopping cycle.

Example of (Dedicated) RRC for Frequency Hopping Configuration

(Dedicated) RRC signaling for frequency hopping configuration mayinclude information on system bandwidth (SRS BW=32 RBs), the number ofconfigured SRS symbols in the SRS transmission slot (N_(SRS_symbol))=2,the start symbol position (or the index) of the configured SRS=8, theend symbol position (or the index) of the configured SRS=9, the partialband index=1, the symbol hopping cycle T_(symbol_hopping)=3 symbols, andthe slot hopping cycle T_(slot_hopping)=2T_(SRS) slots. The hoppinginterval in the time domain MRS may be configured asn_(SRS)=└(l′+N_(SRS_symbol)×└(n_(f)×N_(s)n_(s))/T_(SRS)┘)modT_(symbol_hopping)┘.

Proposal 3

If symbol-level hopping is configured in theperiodic/aperiodic/semipersistent SRS, RRC configuration of the hoppingpattern parameter and DCI configuration of the SRS resource positioninformation may be performed by one of the following operations in orderto support hopping between the partial bands.

The symbol-level hopping pattern parameters including the partial bandindex may be configured/transmitted through RRC signaling. The BS mayconfigure/transmit the partial band index through DCI whenever multipleSRS symbols are transmitted and configure/transmit symbol-level hoppingpattern parameters through RRC signaling. The partial band index may bereplaced with other information indicating the frequency position fordesignating the partial band (e.g., RIV indicating the partial bandposition and range, partial band start RE/RB, and end RE/RB).

FIG. 27 is a diagram illustrating description of Case 1-1.

Case 1: A hopping pattern between SRS symbols is applied in one partialband and hopping to another partial band is performed in a next SRStriggered slot. As Case 1-1, as shown in FIG. 27, the hopping patternbetween symbols in the next SRS triggered slot may be equal to theprevious hopping pattern.

As an embodiment, the symbol-level hopping pattern configurationincluding the partial band index will be described.

In NR, when the number of slots in one frame n _(f) is N_(s), the indexof each slot is n_(s), and l′ is the symbol index of the configured SRS,n_(SRS) for hopping may be configured as shown in Equation 4 below.

$\begin{matrix}{{n_{SRS} = l^{\prime}},{k_{0}^{(p)} = {{\overset{¯}{k}}_{0}^{(p)} + {F\left( {i_{pb},n_{f},n_{s},T_{SRS}} \right)} + {\overset{B_{SRS}}{\underset{b = 0}{\Sigma}}{`K}_{TC}M_{{sc},b}^{RS}n_{b}}}},} & {{Equation}\mspace{14mu} 4}\end{matrix}$

where, F(i_(pb),n_(f),n_(s),T_(SRS)) is a hopping position functionaccording to the partial band index i_(pb). B_(SRS) spans on one partialband.F(i_(pb),n_(f),n_(s),T_(SRS))=(i_(pb)(n_(f),n_(s),T_(SRS))−1)×BW_(pb).BW_(pb) is the number of REs indicating the bandwidth of the partialband. i_(pb)(n_(f),n_(s),T_(SRS))=c(n_(f),n_(s),T_(SRS))mod I_(pb).I_(pb) is a total number of partial bands. c( ) is a scramblingfunction.

As another embodiment, transmission of the partial band index by the BSthrough DCI and the symbol-level hopping pattern will be described.

In Equation 4 above, i_(pb) is transmitted by the BS through DCI in eachslot, in which the SRS is transmitted, and theF(i_(pb),n_(f),n_(s),T_(SRS)) value is configured using i_(pb) .

FIG. 28 is a diagram illustrating description of Case 1-2.

Case 1-2: The information on the hopping pattern may include a valueindicating the partial band index or the partial band (RB and/or RE ofthe partial band), and the BS may configure the information on thehopping pattern in a UE-specific manner. As an embodiment, thesymbol-level hopping pattern configuration including the partial bandindex of FIG. 28 may be expressed as shown in Equation 5 below.

$\begin{matrix}{{n_{SRS} = {l^{\prime} + {N_{{SRS\_ symbo}l} \times \left\lfloor {\left( {{n_{f} \times N_{s}} + n_{s}} \right)/T_{SRS}} \right\rfloor}}},{k_{0}^{(p)} = {{\overset{¯}{k}}_{0}^{(p)} + {F\left( {i_{pb},n_{f},n_{s},T_{SRS}} \right)} + {\sum\limits_{b = 0}^{B_{SRS}}{{`K}_{TC}M_{{sc},b}^{RS}n_{b}}}}},} & {{Equation}\mspace{14mu} 5}\end{matrix}$

where, B_(SRS) spans on one partial band.

The following may be considered in consideration of a repetition symbol.

${n_{SRS} = {\left\lfloor {l^{\prime}/r} \right\rfloor + {{N_{{SRS\_ symbo}l}/r} \times \left\lfloor {\left( {{n_{f} \times N_{s}} + n_{s}} \right)/T_{SRS}} \right\rfloor}}},{k_{0}^{(p)} = {{\overset{¯}{k}}_{0}^{(p)} + {F\left( {i_{pb},n_{f},n_{s},T_{SRS}} \right)} + {\sum\limits_{b = 0}^{B_{SRS}}{{`K}_{TC}M_{{sc},b}^{RS}n_{b}}}}}$

FIG. 29 is a diagram illustrating description of Case 2.

As Case 2, as shown in FIG. 29, the hopping pattern irrelevant to thepartial band in the slot in which multiple SRS symbols are configured isapplicable.

As an embodiment, an example of the hopping pattern irrelevant to thepartial band in the slot in which multiple SRS symbols are configuredmay be expressed as shown in Equation 6 below.

n _(SRS) =l′+N _(SRS_symbol)×└(n _(f) ×N _(s) +n _(s))/T _(SRS) ┘, n_(b) ={n _(b) +F _(b)(n _(SRS))}mod N _(b)   Equation 6

where, B_(SRS) spans full UL BW.

The following may be considered in consideration of a repetition symbol.

n_(SRS)=└l′/r┘+N_(SRS_symbol)/r×└(n_(f)×N_(s)n_(s))/T_(SRS)┘,n_(b)={n_(b)+F_(b)(n_(SRS))}mod N_(b)

FIGS. 30A and 30B are diagrams illustrating description of Case 3.

As Case 3, frequency hopping between the partial bands may bedisallowed. FIG. 30A shows a fixed intra-slot hopping pattern and FIG.30B shows another inter-slot hopping pattern. B_(SRS) may be configuredto span the partial band.

Proposal 4

A method of transmitting information on parameters for inter-slotfrequency hopping configuration supporting hopping between partial bandsin a periodic/aperiodic/semipersistent SRS is proposed.

Proposal 4-1

The BS may configure/transmit information on the SRS frequency resourceposition, the number of the SRS symbols in SRS-triggered slot, the SRSsymbol position, and the position of the transmitted partial band to theUE through RRC signaling (e.g., UE dedicated RRC signaling).

FIG. 31 is a diagram illustrating configuration of a fixed SRS resourceposition at the time of periodic/aperiodic SRS transmission.

The structure of FIG. 31 is possible when only inter-slot hopping in aspecific partial band is supported and can improve SRS receptionperformance through energy combining of the continuously concatenatedSRS symbols.

Proposal 4-2

The BS may configure/transmit information on the SRS frequency resourceposition, the number of the SRS symbols in the SRS-triggered slot, andthe SRS symbol position through RRC signaling (e.g., UE dedicated RRCsignaling) and configure/transmit the transmitted partial band positionthrough DCI.

Proposal 4-3

The BS may configure/transmit information on the SRS frequency resourceposition, the number of the SRS symbols in the SRS-triggered slot, andthe SRS symbol position through RRC signaling (e.g., UE dedicated RRCsignaling) and configure the transmitted partial band position using theinter-slot hopping pattern.

FIG. 32 is a diagram illustrating configuration of hopping betweenpartial bands at the time of periodic/aperiodic triggering.

As shown in FIG. 32, the partial band position may be dynamicallychanged. As an embodiment, an example of the inter-slot hopping pattern(an example of hopping between partial bands) may be expressed as shownin Equation 7 below.

n _(SRS) =└N _(SRS_symbol)×(└n _(f) ×N _(s) +n _(s) ┘/T _(SRS))┘, i_(pb)(n _(SRS))=c(n _(SRS))mod I _(pb)   Equation 7

In consideration of a repetition symbol,n_(SRS)=└N_(SRS_symbol)/r×(└n_(f)×n_(s)n_(s)┘/T_(SRS))┘,

i_(pb)(n_(SRS))=c(n_(SRS))mod I_(pb) may be expressed.

Proposal 4-4

The BS may configure/transmit information on the SRS frequency resourceposition through (dedicated) RRC signaling and configure/transmitinformation on the number of SRS symbols and the partial band positionthrough DCI.

Proposal 4-5

The BS may configure/transmit information on the SRS frequency resourceposition through (dedicated) RRC signaling and configure information onthe number of SRS symbols and the partial band position using theinter-slot hopping pattern.

FIG. 33 is a diagram illustrating configuration of hopping betweenpartial bands at the time of periodic/aperiodic triggering.

As shown in FIG. 33, a structure for flexibly supporting partial bandhopping at the time of SRS transmission and configuring the number ofSRS symbols in the inter-slot hopping parameter configuration may beconsidered.

Proposal 4-6

The BS configures/transmits information on the number of SRS symbols andthe partial band position through (dedicated) RRC signaling andconfigures/transmits information on the SRS frequency resource position(e.g., RIV) through DCI.

Proposal 4-7

The BS may configure/transmit information on the number of SRS symbolsand the partial band position through (dedicated) RRC signaling andconfigure information on the SRS frequency resource position using theinter-slot hopping pattern.

FIG. 34 is a diagram illustrating an example of changing an SRS resourceposition at the time of periodic/aperiodic triggering (a partial band isfixed). As shown in FIG. 34, a structure for prohibiting hopping betweenpartial bands but allowing inter-slot hopping in one partial band isalso possible.

Proposal 4-8

The BS configures/transmits information on the number of SRS symbolsthrough (dedicated) RRC signaling and configures/transmits informationon the partial band position and the SRS frequency resource position(e.g., MV) through DCI.

Proposal 4-9

The BS configures/transmits information on the number of SRS symbolsthrough (dedicated) RRC signaling and configures information on thepartial band position using the inter-slot hopping pattern. The BSconfigures/transmits information on the SRS frequency resource position(e.g., MV) through DCI.

Proposal 4-10

The BS configures/transmits information on the number of SRS symbolsthrough (dedicated) RRC signaling and configures information on thepartial band position and the SRS frequency resource position (e.g., MV)using the inter-slot hopping pattern.

FIG. 35 is a diagram illustrating an example of changing an SRS resourceposition at the time of periodic/aperiodic triggering (a partial band isvariable).

FIG. 35 shows a configuration for allowing partial band hopping betweenSRS slots while the number of SRS symbols in the slot between UEs isfixed (that is, the number of energy combining symbols is fixedaccording to a received signal difference according to a distancebetween the UE and the BS).

Proposal 5

For UL resource allocation of the UL full band or UL SRS partial band ofthe UEs each having a narrow band RF, a predetermined number of symbols(n symbols) of the configured SRS symbols is emptied to apply a retuningtime at the time of intra-slot hopping. However, n is less than thenumber L′ of symbols of the configured SRS. Since the n value may bedetermined according to retuning delay of the UEs each having a narrowband RF, the UEs each having the narrow band RF may report the retuningdelay value to the BS. The BS may indicate to the UE how many SRSsymbols are emptied at which position in all the SRS symbols, based onthe report.

Proposal 5-1

The BS may configure/transmit information on the position of the emptysymbol in the configured SRS slot through cell-specific RRC signaling.

The BS may collectively empty the specific SRS symbol without the RFcapability report from the UEs and the emptied symbols may be used forother UL channels. Accordingly, symbol-level hopping may be basicallyconfigured to be performed in the localized resource SRS at the emptiedsymbol boundary.

Proposal 5-2

The BS may configure/transmit the position of the empty symbol in theconfigured SRS slot through UE-dedicated RRC signaling.

Proposal 5-3

The BS may start emptying at an emptying start position l′₀ within thesymbol l′≤L′ configured for the position of the empty symbol in theconfigured SRS slot and transmit the symbol index l′₁ for transmissionof the SRS symbol to the UE again. At this time, a relationship ofl′₀≤l′₁≤L′ is satisfied.

Proposal 5-4

The RF capability (the transmission RF degree covering the full orpartial UL band and/or the RF retuning degree) of the UE may be reportedto the BS. The BS may transmit the position of empty symbols, the numberof empty symbols, and the number of configured SRS symbols to the UEthrough RRC, MAC-CE or DCI in a UE-specific manner according to theintra-slot hopping pattern when multi-SRS symbols are triggered(periodic/aperiodic/semipersistent).

FIGS. 36A and 36B are diagrams illustrating an intra-slot hoppingpattern considering RF retuning of a UE having narrow band RFcapability.

FIG. 36A shows the SRS BW and RF BW capability of a specific UE and FIG.36B shows 1-symbol retuning in the capability of FIG. 36A.

The present disclosure proposes a configuration and method for enablingUEs (e.g., cell-edge UEs), which cannot perform UL full-bandtransmission due to limitation of UE's link budget, to perform ULfull-band sounding while subband sounding hops on multiple symbols ormultiple slots if UL full-band sounding is requested at the time of NRSRS transmission. Such an SRS hopping configuration and method may beused not only for UL resource allocation but also for UL beammanagement. The present disclosure proposes an SRS hopping configurationmethod considering RF retuning in order to support hopping of NR UEshaving narrow band RF capability.

Proposal 6 (SRS Counter Related to SRS Transmission)

B_(SRS) may have a value of {0, 1, 2, 3} as a parameter indicating SRSbandwidth and b_(hop) may have a value of {0, 1, 2, 3} as a parameterindicating SRS frequency hopping bandwidth. The BS may transmit thevalues of (or information on) B_(SRS) and b_(hop) to the UE through RRCsignaling. r denotes the repetition number of symbol(s) configured forSRS transmission and r=1, 2, or 4. The BS may transmit the value of r tothe UE through RRC signaling.

An SRS transmission timing equation for applying intra-slot hopping torepetition symbol configuration in one slot may be represented as inEquation 8 below in which n_(SRS) denotes an SRS counter related to SRStransmission.

$\begin{matrix}{n_{SRS} = {\left\lfloor {l^{\prime}/r} \right\rfloor + {\frac{N_{symbol}}{r} \times \left\lfloor {\left( {{n_{f} \times N_{s}} + n_{s}} \right)/T_{SRS}} \right\rfloor}}} & {{Equation}\mspace{14mu} 8}\end{matrix}$

where N_(symbol) denotes the number of SRS symbols configured in oneslot. N_(s) denotes the number of slots in one radio frame. l′ denotes asymbol index {0, . . . ,N_(symbol)−1} for which an SRS is configured.n_(f) denotes a radio frame index, and n_(s) denotes a slot index in oneradio frame. T_(SRS) denotes a UE-specific SRS transmission cycle and rdenotes the repetition number of SRS symbols in a slot.

According to configuration of the repetition number r of symbols, on/offof intra-slot hopping or on/off of a repetition symbol may bedetermined.

Case of r=1

When r=1, intra-slot hopping or inter-slot hopping may be operated orperformed according to the relationship between B_(SRS) (parameterindicating SRS bandwidth) and b_(hop) (parameter indicating SRSfrequency hopping bandwidth) (if B_(SRS)≤b_(hop), frequency hopping maynot be enabled and, if B_(SRS)>b_(hop), frequency hopping may beenabled).

Case of r=2

When r=2, whether to perform intra-slot hopping or inter-slot hoppingmay be determined according to the number of SRS symbols allocated to acorresponding slot. When N_(symbol) is 2, intra-slot hopping becomesoff. When N_(symbol) is 4, intra-slot hopping may be performed in agroup of two symbols.

Case of r=4

When r=4 and N_(symbol) is 4, intra-slot hopping becomes off andinter-slot hopping may become on or off according to the relationshipbetween B_(SRS) and b_(hop). When r=4 and N_(symbol) is 2, sincer>N_(symbol), SRS configuration may be interpreted as being modified.That is, although the UE receives information on r=4 from the BS, the UEmay interpret the relationship of r>N_(symbol) as r=2. Accordingly,intra-slot hopping becomes off and inter-slot hopping may become on oroff according to the relationship between B_(SRS) and b_(hop). Forexample, when B_(SRS)≤b_(hop), inter-slot hopping may not be enabled(i.e., off) and, when B_(SRS)>b_(hop), inter-slot hopping may be enabled(i.e., on).

When N_(symbol) is 2, although r>N_(symbol), r=4 may mean the repetitionnumber of symbols over a slot. In this case, although intra-slot hoppingbecomes off, inter-slot hopping may become on or off according to therelationship between B_(SRS) and b_(hop) in units of a specific slotgroup (the repetition number of slots is greater than 2). For example,when B_(SRS)≤b_(hop), inter-slot hopping may not be enabled (i.e., off)and, when B_(SRS)>b_(hop), inter-slot hopping may be enabled (i.e., on).

Case of r>4

When r>4, since the relationship of r>N_(symbol) is always satisfied(because N_(symbol) is any one of 1, 2, and 4), configuration needs tobe interpreted as being modified. When Nsymbol=2, although the UEreceives information of r=4 from the BS, the UE needs to interpret thereceived information as r=2. Accordingly, intra-slot hopping may becomeoff and inter-slot hopping may become on or off according therelationship between B_(SRS) and b_(hop). For example, whenB_(SRS)≤b_(hop), inter-slot hopping may not be enabled (i.e., off) and,when B_(SRS)>b_(hop), inter-slot hopping may be enabled (i.e., on).

When r>4 and N_(symbol)=2, the UE may interpret the repetition number ofsymbols over a slot as being greater than 4. Accordingly, althoughintra-slot hopping becomes off, inter-slot hopping may be on or offaccording to the relationship between B_(SRS)and b_(hop) in units of aspecific slot group (the repetition number of slots (slots in which anSRS is repeatedly transmitted) is greater than 2). For example, whenB_(SRS)<b_(hop), inter-slot hopping may not be enabled (i.e., off) and,when B_(SRS)>b_(hop), inter-slot hopping may be enabled (i.e., on).

Procedure of Transmitting SRS by UE in Relation to Proposal 6

FIG. 37 is a diagram illustrating a procedure of transmitting an SRS bya UE in relation to Proposal 6.

Referring to FIG. 37, the UE may receive first information on the numberof SRS symbols configured in one slot and second information on therepetition number of symbols configured for SRS transmission from theBS. The UE may determine whether the repetition number of symbolsconfigured for SRS transmission is greater than the number of SRSsymbols configured in one slot. If the repetition number of symbolsconfigured for SRS transmission is greater than the number of SRSsymbols configured in one slot, the UE may determine the repetitionnumber of symbols configured for SRS transmission as a value equal tothe number of SRS symbols configured in one slot. The UE may transmitthe SRS based on the determined repetition number of symbols configuredfor SRS transmission.

The UE may further receive information on a first parameter valueB_(SRS) indicating SRS bandwidth and information on a second parametervalue b_(hop) indicating SRS frequency hopping bandwidth from the BS. Ifthe first parameter value is greater than the second parameter value,the UE may transmit the SRS by (frequency-)hopping the SRS at a slotlevel.

If the determined repetition number of symbols configured for SRStransmission is a repetition number over at least two slots, the UE maytransmit the SRS over at least two slots. Unlike this case, if thedetermined repetition number of symbols configured for SRS transmissionis a repetition number over one slot, the UE may transmit the SRS overone slot without performing frequency hopping. The UE may receive thefirst information, the second information, the information on the firstparameter value B_(SRS), and the information on the second parametervalue b_(hop), in FIG. 37, through RRC signaling.

Procedure of Receiving SRS by BS in Relation to Proposal 6

FIG. 38 is a diagram illustrating a procedure of receiving an SRS by aBS in relation to Proposal 6.

Referring to FIG. 38, the BS may transmit first information on thenumber of SRS symbols configured in one slot and second information onthe repetition number of symbols configured for SRS transmission to theUE. If the repetition number of symbols configured for SRS transmissionis greater than the number of SRS symbols configured in one slot, the BSmay determine (or recognize) the repetition number of symbols configuredfor SRS transmission as a value equal to the number of SRS symbolsconfigured in one slot. The BS may receive the SRS based on thedetermined repetition number of symbols configured for SRS transmission.

The BS may transmit information on a first parameter value B_(SRS)indicating SRS bandwidth and information on a second parameter valueb_(hop) indicating SRS frequency hopping bandwidth to the UE. If thefirst parameter value is greater than the second parameter value, the BSmay receive the SRS which is frequency-hopped at a slot level. If thedetermined repetition number of symbols configured for SRS transmissionis a repetition number over at least two slots, the BS may receive theSRS over at least two slots. Unlike this case, if the determinedrepetition number of symbols configured for SRS transmission is arepetition number over one slot, the BS may receive the SRS over oneslot in the form of not being frequency-hopped. The BS may transmit thefirst information, the second information, the information on the firstparameter value BSRS, and the information on the second parameter valueb_(hop) to the UE through RRC signaling.

FIG. 39 is a block diagram of a UE for transmitting an SRS and a BS forreceiving an SRS in relation to Proposal 6.

UE for transmitting SRS in relation to Proposal 6

Referring to FIG. 38, a receiver 23 of the UE may receive firstinformation on the number of SRS symbols configured in one slot andsecond information on the repetition number of symbols configured forSRS transmission from the BS. A processor 21 of the UE may determinewhether the repetition number of symbols configured for SRS transmissionis greater than the number of SRS symbols configured in one slot. If therepetition number of symbols configured for SRS transmission is greaterthan the number of SRS symbols configured in one slot, the processor 21may determine the repetition number of symbols configured for SRStransmission as a value equal to the number of SRS symbols configured inone slot. A transmitter 23 of the UE may transmit the SRS based on thedetermined repetition number of symbols configured for SRS transmission.The receiver 23 of the UE may receive information on a first parametervalue B_(SRS)indicating SRS bandwidth and information on a secondparameter value b_(hop) indicating SRS frequency hopping bandwidth fromthe BS. If the first parameter value is greater than the secondparameter value, the processor 21 of the UE may control the transmitter23 to transmit the SRS by hopping the SRS at a slot level. The receiver23 of the UE may receive the first information, the second information,the information on the first parameter value BSRS, and the informationon the second parameter value b_(hop) from the BS through RRC signaling.

BS for Receiving SRS in Relation to Proposal 6

A transmitter 13 of the BS may transmit first information on the numberof SRS symbols configured in one slot and second information on therepetition number of symbols configured for SRS transmission to the UE.If the repetition number of symbols configured for SRS transmission isgreater than the number of SRS symbols configured in one slot, aprocessor 11 of the BS may determine or recognize the repetition numberof symbols configured for SRS transmission as a value equal to thenumber of SRS symbols configured in one slot. A receiver 13 of the BSmay receive the SRS based on the determined repetition number of symbolsconfigured for SRS transmission. The transmitter 13 of the BS maytransmit information on a first parameter value indicating SRS bandwidthand information on a second parameter value indicating SRS frequencyhopping bandwidth to the UE. If the first parameter value is greaterthan the second parameter value, the receiver 13 of the BS may receivethe SRS in the form of being (frequency-)hopped at a slot level.

If the determined repetition number of symbols configured for SRStransmission is a repetition number over at least two slots, thereceiver 13 of the BS may receive the SRS over at least two slots.Unlike this case, if the determined repetition number of symbolsconfigured for SRS transmission is a repetition number over one slot,the receiver 13 of the BS may receive the SRS over one slot in theformed of not being frequency-hopped. The transmitter 13 of the BS maytransmit the first information, the second information, the informationon the first parameter value BSRS, and the information on the secondparameter value b_(hop) to the UE through RRC signaling.

Definition of Repetition Number of Slots

As another embodiment, the repetition number of slots may be defined.The repetition number of slots means the number of slots in whichrepetition for SRS transmission is performed. Accordingly, intra-slothopping, inter-slot hopping, symbol-level repetition, or slot-levelrepetition may be performed by a combination of the repetition number Rof slots and the repetition number r of symbols. Equation 9 belowindicates n_(SRS) considering the repetition number R of slots.

$\begin{matrix}{n_{SRS} = {\left\lfloor {l^{\prime}/r} \right\rfloor + {\frac{N_{symbol}}{r} \times \left\lfloor {\left( {{n_{f} \times N_{s}} + n_{s}} \right)/\left( {R \times T_{SRS}} \right)} \right\rfloor}}} & {{Equation}\mspace{14mu} 9}\end{matrix}$

where N_(symbol) denotes the number of SRS symbols configured in oneslot. N_(s) denotes the number of slots in one radio frame. l′ denotes asymbol index {0, . . . ,N_(symbol)−1} configured for SRS transmission.n_(f) denotes a radio frame index, and n_(s) denotes a slot index in oneradio frame. T_(SRS) denotes a UE-specific SRS transmission cycle and rdenotes the repetition number of SRS symbols in a slot. R denotes thenumber of slots in which repetition for SRS transmission is performed.

In this case, the value of r may be limited according to the number ofsymbols in a slot. When N_(symbol)=4, r may be {1,2,4} and, whenN_(symbol)=2, r may be {1,2}.

The aforementioned embodiments are achieved by combination of structuralelements and features of the present disclosure in a predeterminedmanner. Each of the structural elements or features should be consideredselectively unless specified separately. Each of the structural elementsor features may be carried out without being combined with otherstructural elements or features. Also, some structural elements and/orfeatures may be combined with one another to constitute the embodimentsof the present disclosure. The order of operations described in theembodiments of the present disclosure may be changed. Some structuralelements or features of one embodiment may be included in anotherembodiment, or may be replaced with corresponding structural elements orfeatures of another embodiment. Moreover, it will be apparent that someclaims referring to specific claims may be combined with other claimsreferring to the other claims other than the specific claims toconstitute the embodiment or add new claims by means of amendment afterthe application is filed.

Those skilled in the art will appreciate that the present disclosure maybe carried out in other specific ways than those set forth hereinwithout departing from the spirit and essential characteristics of thepresent disclosure. The above exemplary embodiments are therefore to beconstrued in all aspects as illustrative and not restrictive. The scopeof the disclosure should be determined by the appended claims and theirlegal equivalents, not by the above description, and all changes comingwithin the meaning and equivalency range of the appended claims areintended to be embraced therein.

The method of transmitting and receiving an SRS and the communicationapparatus therefor may be industrially applicable to various wirelesscommunication systems such as a 3GPP LTE/LTE-A system and an NR (5G)communication system.

What is claimed is:
 1. A method of transmitting a sounding referencesignal (SRS) by a user equipment (UE), the method comprising: receiving,from a base station (BS), first information on (i) a number of SRSsymbols configured in one slot and (ii) a repetition number of symbolsconfigured for SRS transmission; receiving, from the BS, secondinformation on (i) a first parameter value related to SRS bandwidth and(ii) a second parameter value related to SRS frequency hoppingbandwidth; and transmitting the SRS based on the first information andthe second information, wherein, based on whether the first parametervalue is greater than the second parameter value, frequency hopping ofthe SRS is enabled.
 2. The method of claim 1, wherein the repetitionnumber of symbols configured for SRS transmission is R, and the numberof SRS symbols configured in the one slot is N, and wherein whether theSRS is transmitted with intra-slot frequency hopping and whether the SRSis transmitted with inter-slot frequency hopping are determined based onvalues of the N and the R.
 3. The method of claim 1, wherein therepetition number of symbols configured for SRS transmission is arepetition number over at least two slots, and wherein the SRS istransmitted over the at least two slots.
 4. The method of claim 1,wherein the repetition number of symbols configured for SRS transmissionis a repetition number over the one slot, and wherein the SRS istransmitted over the one slot without the frequency hopping.
 5. Themethod of claim 1, wherein the SRS symbols are adjacent symbols, whereinthe N is one of 1, 2, and 4, and the R is one of 1, 2, or
 4. 6. A userequipment (UE) configured to transmit a sounding reference signal (SRS),the UE comprising: a receiver; a transmitter; and a processor, whereinthe receiver is configured to receive , from a base station (BS), firstinformation on (i) a number of SRS symbols configured in one slot and(ii) a repetition number of symbols configured for SRS transmission, andsecond information on (i) a first parameter value related to SRSbandwidth and (ii) a second parameter value related to SRS frequencyhopping bandwidth, wherein the transmitter is configured to transmit theSRS based on the first information and the second information, andwherein, based on whether the first parameter value is greater than thesecond parameter value, frequency hopping of the SRS is enabled.
 7. TheUE of claim 6, wherein the repetition number of symbols configured forSRS transmission is R, and the number of SRS symbols configured in theone slot is N, and wherein whether the SRS is transmitted withintra-slot frequency hopping and whether the SRS is transmitted withinter-slot frequency hopping are determined based on values of the N andthe R.
 8. The UE of claim 6, wherein the repetition number of symbolsconfigured for SRS transmission is a repetition number over at least twoslots, and wherein the SRS is transmitted over the at least two slots.9. The UE of claim 6, wherein the repetition number of symbolsconfigured for SRS transmission is a repetition number over the oneslot, and wherein the SRS is transmitted over the one slot without thefrequency hopping.
 10. The UE of claim 6, wherein the SRS symbols areadjacent symbols, wherein the N is one of 1, 2, and 4, and the R is oneof 1, 2, or
 4. 11. A computer readable storage medium, wherein thecompute readable storage medium is configured to store at least onecomputer program including instructions for causing, when executed by atleast one processor, the at least one processor to perform an operationfor a user equipment, wherein the operation includes: receiving, from abase station (BS), first information on (i) a number of SRS symbolsconfigured in one slot and (ii) a repetition number of symbolsconfigured for SRS transmission; receiving, from the BS, secondinformation on (i) a first parameter value related to SRS bandwidth and(ii) a second parameter value related to SRS frequency hoppingbandwidth; and transmitting the SRS based on the first information andthe second information, wherein, based on whether the first parametervalue is greater than the second parameter value, frequency hopping ofthe SRS is enabled.
 12. The computer readable storage medium of claim11, wherein the repetition number of symbols configured for SRStransmission is R, and the number of SRS symbols configured in the oneslot is N, and wherein whether the SRS is transmitted with intra-slotfrequency hopping and whether the SRS is transmitted with inter-slotfrequency hopping are determined based on values of the N and the R. 13.The computer readable storage medium of claim 11, wherein the repetitionnumber of symbols configured for SRS transmission is a repetition numberover at least two slots, and wherein the SRS is transmitted over the atleast two slots.
 14. The computer readable storage medium of claim 11,wherein the repetition number of symbols configured for SRS transmissionis a repetition number over the one slot, and wherein the SRS istransmitted over the one slot without the frequency hopping.
 15. Thecomputer readable storage medium of claim 11, wherein the SRS symbolsare adjacent symbols, wherein the N is one of 1, 2, and 4, and the R isone of 1, 2, or 4.